Since it's the trendy thing to do, and it seems the public has an insatiable appetite for it, I thought I'd throw my hat in the ring on the spoilers from the much-anticipated Magic 2011 Core Set. Strap in for the long haul, because I'm covering every relevant card so far revealed!
White
Angelic Arbiter – The Timmy in me loves big creatures will splashy effects. I think the Arbiter has an incredibly powerful effect, but may not find a true home. While plenty of decks play both spells and want to attack, most decks have a Stage 3 that is one or the other. Grixis may play both dudes and spells, but it's ending with Cruel Ultimatum. In that sense, Angelic Arbiter is inferior to Iona, Shield of Emeria. I think if the Angelic Arbiter finds a home anywhere, it will be in Reanimator, as a hybrid between Blazing Archon and Iona. I wonder if the hybrid will be good enough, or if either of the former choices proves more potent.
Condemn – I'm extremely happy to see this card replace Path to Exile. I thought Path was perhaps a bit too oppressive as it allowed traditionally reactive control deck get a very proactive spell, able to kill creatures the turn you played them, which hurt a lot of creatures that either had static effects (Joraga Warcaller, Rafiq of the Many, Siege-Gang Commander) or ones that required untapping to get the effect (Knight of the Reliquary). I prefer this version as a more balanced offering, though I rue the 3 months where U/W gets both. Sorry, Conscription Mythic!
Sun Titan – I'm surprised to see how much unsure murmuring has surrounded this card. There's a few solid principles of Magic: free stuff is good, tutoring is good, etc. Every set there's some card that follows fundamental rules of Good Magic Cards and people still hesitate because they don't see an immediate use. Stoneforge Mystic was received coolly, or often not even mentioned (go back and look at WW set reviews, no mention of it usually) and yet it was a fundamentally Good Magic Card. For 2, you got to tutor up any artifact, and next turn play it (avoiding counterspells) for only 1W. Now, Stoneforge Mystic was one of the breakout cards of the set and even sees play in Legacy.
What does this have to do with Sun Titan?
In Magic, stuff dies. A lot. Tarmogyf is good without you needing to go out of your way to pump it up. Just in the current standard environment, cards like Knight of the Reliquary, Dauntless Escort, and Qasali Pridemage find themselves in the graveyard often, and recurring them even once is a high value play (as a 6/6 Vigilance is perfectly acceptable, so getting a free dude is awesome). Not to mention fetchlands and Tectonic Edge, or Oblivion Ring, or even Jace Beleren. While not as focused as the other Titans, Sun Titan is incredibly potent. If you recur a fetchland, he's a worse Primeval Titan. If you get a Qasali Pridemage, he's a situationally worse Grave Titan. But the important part is that he's flexible enough to fill several roles depending on the deck, and that makes his potential nothing short of exciting.
Blue
Conundrum Sphinx – I can't believe a card this good may not see competitive play. Oracle of Mul Daya sees play nearly strictly on the interaction with Jace, The Mind Sculptor. You see, you use Brainstorm to put lands on top, then play them with the Oracle to dig deeper into the deck so on your next turn you Brainstorm for all new cards. Conundrum Sphinx works that interaction on an efficient beater's body. By Brainstorming then naming that card, you will dig deeper and deeper, stacking your hand with answers. Like Frost Titan, I wonder if cards like Sphinx of the Jwar Isle are just better, and how much being 4-cost will hurt this card. So many other solid 4-drops push this card to the fringe of playability, and that blows my mind because any Magic player from 1996 would crap their pants at the power level of this card. How far creatures have come.
Diminish – This caught my eye because it's likely the closest Blue is going to get to creature kill in M11. While not as good as Snakeform for the same reason that Convincing Mirage isn't as good as Spreading Seas, I think it's a solid combat trick for Limited that may see sideboard play.
Frost Titan – This is the most underwhelming of the Titan cycle, but for overall positive reasons. Blue simply has an overabundance of efficient beaters that count as win conditions. That seems weird to say, but Blue already has exceptional end-game creatures like Sphinx of the Jwar Isle and Sovereigns of Lost Alara. Frost Titan's first ability is to hopefully prevent spot removal from being efficient, and the second, by the time you have 6 mana, is likely going to lock down creatures/blockers to win a race.
Compared to the Sphinx of Jwar Isle, Shroud is better because it absolutely prevents spot removal, and Flying is likely to be better than tapping defenders, since it's naturally evasive anyways. Frost Titan may have it's supporters, and it's close enough that it will see some play, but I can't help but think Blue and U/x decks will find best finishers elsewhere.
Jace's Ingenuity – The community seems to be somewhat split on this card. Paying to draw 3 cards as a sorcery would be absolutely awful, but at Instant could be really solid. It's hard to evaluate this card because it's usability is reliant on every other card in the meta more than its own merits. For example, U/W Control made the first splash in Standard from Chapin's deck at Pro Tour San Diego. It was very much an old-school control deck with a lot of counterspells and attempting to play a more Draw-Go gameplan.
Mana Leak – A thousand words have already been written about this card already so I won't repeat them, but I will say this: Anyone complaining about mythic rares, planeswalkers, and the price of Standard should kiss this card's feet. Planeswalkers are pretty much the most powerful cards you can play, and currently have limited efficient answers. Hasty creatures like Bloodbraid Elf are okay, but they still allow the Planeswalker to take at least 1 action, then soak up some damage. Negate is the best answer since it's mana efficient, often Time Walks them, and prevents the Planeswalker from taking an ability.
Jace, The Mind Sculptor is pushing $100. Mana Leak is 75 cents. Mana Leak trumps Jace. Mana Leak is splashable so that it can appear in plenty of decks, including aggro decks. Mythic will find room for it, Beastmaster Green can easily splash blue for a bit of disruption. Hell, RDW was splashing black just for Blightning and Terminate, if the rumors of enemy color dual lands are true, I could see RDW with a blue splash for Mana Leak, Distortion Strike, and other blue disruption. If you're sick of expensive cards, Mana Leak is going to be about as cheap as they come and it's going to answer them all.
Time Reversal – I've been sworn to secrecy on this card. Just let me tell you, Pros are excited about this Mythic. It's situational, requires itself to be built around, and very meta-dependent. You know what else is? Vengevine. Go ahead and pick some up.
Black
Captivating Vampire – While Vampire Nocturnus was bad mechanically (too hit or miss) and badly developed (Mythic rare for a tribe made for the casual crowd), I don't feel this card is a suitable replacement. The tap ability is brutal for a tribe without token generation, I almost feel like I could get off Lullmage Mentor's ability before this guy. Vampires were already a sketchy deck in Standard, I think losing Nocturnus and only having Captivating Vampire as a lord will be the death knell of the deck in competitive circles.
Grave Titan – I could see this being a great card for Mono Black or B/x Control. Black contains several powerful cards, but no good way to generate card advantage. Your removal trades one-for-one, and current win conditions like Abyssal Persecutor and Nightmare put all your eggs in one basket. Grave Titan frees up space for more control cards, and even if they kill him, you have four power of creatures to put a bit of a clock on them, or ensure Jace, The Mind Sculptor's survival to get you back on your feet.
Phylactery Lich – Like everyone else, I am required by law to say this card oozes flavor. Mono Black Control gets another solid tool, as they already run Everflowing Chalice. Play the Chalice on 2, setting up for a Consuming Vapors on turn 3, or if they haven't really threatened the board, play this guy. Another solid finisher for Black control decks, I wonder if it'll be enough to make U/B Control a viable option. This guy may have to wait for Scars of Mirrodin to truly break out, but if Everflowing Chalice isn't a good enough artifact for this guy, what is?
Red
Combust – I have a feeling that the designers of M11 took to heart all the complaints about power Mythics and set out to present a lot of solid (but balanced) answers. Ignite Disorder was flat-out awful, but Combust will see plenty of play for the next 15 months. For , you get "Destroy target Baneslayer Angel." Also works on a beefy Knight of the Reliquary, Conundrum Sphinx, Sovereigns of Lost Alara, Rhox War Monk, and Linvala, Keeper of Silence. There is more than enough commonly played targets for this to push garbage like Unstable Footing out of mono-Red sideboards.
Ember Hauler – This card is hard to evaluate. In a vacuum I think it's great. Red Deck variants all tend to rush with 1-2 cost creatures, and once you stabilize, dump a hand full of burn to finish the job. Under that criteria, Ember Hauler is amazing! Sadly, (or amazingly, depending on your viewpoint), Red Deck has an abundance of great two-drops. The question is not whether Ember Hauler is good, it's whether it's better than Kargan Dragonlord, Plated Geopede, Kiln Fiend, etc. I expect to see this Goblin in the black splash RDW decks, that don't run Geopede due to a lack of fetchlands. He seems about on-par with Kiln Fiend, and that saw a fair amount of play.
Fling – A Limited high-pick given the format is riddled with generic creatures, but it'll be interesting to see how the card works with the M10 Rules Change. Before, you could put damage on the stack then Fling the creature, essentially doubling its power. The new rules are a huge decrease in the power, but that didn't stop Siege-Gang Commander (another M10 stud who won't be in M11) from being good. With all the good burn Red Deck has now, I don't think it'll find a spot. However, upon Scars of Mirrodin's release Standard will be a small environment and Fling may be good enough at that point.
Inferno Titan – I'm also surprised to see so much excitement about this guy. By the time you hit six mana (especially as Red, which lacks mana acceleration), what do you intend on killing? Certainly there will be a juicy target from time to time, but its keyword (Firebreathing) is worse than Trample, Vigilance, and probably even Frost Titan's Rune Snag effect. The burn effect is solid, but I wonder how powerful it will be in Standard relative to the other Titans. I think this is the weakest of them in Constructed, but the most powerful in Limited.
Green
Back to Nature – I always like to see classic cards revamped to make them more cost-appropriate. While Standard isn't dying for mass-enchantment removal, having it as an answer is a solid pre-emptive maneuver. This will be great for EDH however, a format with plenty of powerful enchantments and not enough reset buttons for non-creature permanents. Glad it's splashable too, as even being would keep it out of numerous sideboards.
Cultivate – Count me amoung the lovers of this card. It's not broken, or even particularly amazing, but we've all missed that crucial land drop in our Magic career, and in smaller formats like Standard, cards that serve a function while replacing themselves will find a home. I mean, a deck that some consider the Best Deck in Standard runs 4 copies of friggin' Sea Gate Oracle. Another argument against it is that ramping from 2 -» 4 is better than 3 -» 5 due to the strengths of the format's four drops. That's fair, but most of those four drops are in Alara, and post-Alara 5 mana cards like Gideon Jura and Baneslayer Angel can swing games, and with a bevy of strong 6-drops being introduced, I think ramping past the crucial 4 spot and into the big beef will be a legitimate line of play.
Mitotic Slime – We all hate Sprouting Thrinax. This is a 'fair' Thrinax. Will it be good enough? A feel cute synergies exist, like Momentous Fall, but like Thrinax it's a bit of a bland creature and if they have a larger creature, the Slime will never be able to overcome it. It's a solid bit of card advantage for Green decks and defense against Day of Judgment, but overall I think that for 5 mana even a Mono Green deck can find something more powerful to do. This guy could very likely become a Limited bomb in a format dominated by efficient vanilla creatures and limited removal, although being a rare limits his impact.
Obstinate Baloth – I've gone through several feelings on this guy. At first sight, I scoffed happily at thinking of countering a Blightning with it. I thought it was awesome. Then I thought about it more, and wondered what decks would actually run it, and changed my opinion to being underwhelmed and thinking it being a niche card at best. Then I looked at Turboland decks and thought how their best out to RDW archetypes is Pelakka Wurm. Pelakka Wurm, if resolved, is a total beating against any archetype looking to burn you out late game. However, most creatures with ETB life gain have sub-optimal bodies or exist at extremes on the curve. Lone Missionary is too small to be a relevant piece on the board, and the Wurm (even for Turboland) comes too late to save you.
Enter Obstinate Baloth.
RDW and Jund are excellent at hitting your mana dorks and keeping you off balance with your mana. Mythic has a hard time hitting or without Noble Hierarch, Birds of Paradise, and Lotus Cobra. Kor Firewalker isn't a guaranteed turn two play, especially given how many of its white sources come into play tapped. Against Jund, Firewalkers are nice but they don't threaten the board or realistically put your opponent on a clock either. For Turboland, even with all the ramp in the world, hitting seven lands is hard when your Oracles of Mul Daya are eating Lightning Bolt. Obstinate Baloth fits absolutely perfectly in that mid-range gap. Turboland can always hit 4 lands, Mythic can always hit , and both decks are hurting for post-board answers for Jund and RDW. I think Obstinate Baloth is still slightly overhyped, but he's an incredibly needed card that is perfectly costed and statted to fit into existing archetypes.
Overwhelming Stampede – I really dislike this card. I get that Overrun can be boring and change is good, but this seems just awful. Overrun decks were about spamming creatures that were generally small, to maximize the number of bonuses. I suppose it's not terribly unlikely to have a 3-power creature somewhere in the mix, but I feel like for strategies like Elfball, it will be a struggle to make it equal to the always-consistent Overrun.
Plummet – Like White, Green has all too often had a segment of the color pie that was too restrictive and resulted in long periods of 'meh' feelings towards the color. Not having creature kill or counterspells always resulted in them having trouble with nearly every deck. I'm glad they are expanding Green 'no removal' to be less absolute and more situational. Slingbow Trap was always a fringe sideboard card, and now Green has a legitimate sideboard for difficult creatures like Baneslayer Angel and Malakir Bloodwitch.
Primeval Titan – I don't think words can describe how good I think this guy is. But let me try. Conscription Mythic plays about as much ramp as a creature deck can reasonably field, and it consistently ramps up to around 5 (Baneslayer Angel) and 6 (Sovereigns of Lost Alara). But let's say you want a bigger trump and decide to go for Eldrazi. Be able to fetch any land (not just basics) means you can grab say, your singleton Eye of Ugin and an Eldrazi Temple, ramping from 6 to 10/11. This guy is a threat on his own, forces your opponent to deal with him, and simply resolving him sets you up for the huge aliens. Ramp decks all too often can ramp to the mid-game but have difficulty getting over that hump to the late game, hence why Turboland stops at Avenger of Zendikar. This guy provides not only a solid threat, but a seamless stepping stone to the real fatties. I feel this guy is the best of the Titan cycle and will easily settle into the $20-$30 price range he's currently being pre-sold at.
Sylvan Ranger – I think this guy is being fairly underrated. Elvish Visionary sees play and this guy is pretty often an upgrade, as on turn 2 you're often looking to curve out. Borderland Ranger sees play and this guy is better because by turn 3 you want to start playing more relevant spells instead of fixing your land, plus the Ranger is an Elf. He's not flashy, but a solid role player in an archetype that is just waiting for the rotation (Eldrazi Green).
Artifacts
Temple Bell – This card makes the game designer in me smile. Howling Mine was a great engine card that fueled many decks, but from a judge / rules standpoint was a headache. How many missed triggers and forgotten draws occurred from Howling Mine over the course of its life? Probably over 100,000 cards went undrawn under the harsh lights of tournament play, ones just missed or forgotten. Now, how many missed draws occur from Jace Beleren's +2 ability? Practically none. It's activated, announced, and resolved. Very simple, fills the same role, and can lead to some trickiness with…
Voltaic Key – Hey yo! One of Vintage's most broken enablers, I don't think you'll see much of the same problems combos in the current Standard. Cards like Thran Dynamo and Grim Monolith just don't exist anymore, shelved as too broken and exploitable. This is a splashy and newsworthy reprint, but overall I think without anything (besides Temple Bell) to untap, it will be relatively quiet in the metagame. If Scars of Mirrodin reprints Mana Vault however, I'll eat my words.