I haven't been able to play a lot of the new games I got over Christmas because I've been spending the last few days messing with video encoding settings.

I really need to finish Portal 2 co-op (nearly done) & Serious Sam 3, and spend a lot more time with KoFXIII, UMvC3, and Eschatos. But so far, my top 10 is:
1. Akai Katana Shin - Three great games in one. Shin is the best console mode Cave has come up with, Zetsu is a perfect rebalance of the arcade version to take advantage of the 360's additional power, and Arcade is still great in its own right (though it's the weakest of the bunch). Then there's great art, great graphics, and the best original soundtrack of the generation.
2. Dark Souls - I haven't played 1.05 yet, but this was still a nice evolution of the Demon's Souls formula. I was wary about the open world when they first announced it, since open world games usually involve lots of tedious traveling in between the fun parts, but I think it worked really well here because exploration is a huge part of the game. The online component was a big step back over the dedicated servers from the original, and a few of the stages suck, but I guess that's to be expected because the game has an incredible amount of content. Still a great sequel to one of the best games this gen.
3. Hard Corps Uprising - They could've trimmed the game down a little more, because it's really fucking long (1-1.5 hours), but I can't say I mind too much since almost all of its content is fantastic - just like Metal Slug 3. One of the best things about the game is that it has a relatively complex control scheme, and it's put to good use because the stages are designed around making the player take advantage of these options. It looks great, it sounds great, it plays well online, it's challenging, and it's a great value. Couldn't ask for much more than that.
4. Catherine - The best puzzle game of the generation. There's some incredible variety here, between all of the block types and new formations that you're constantly faced with. Atlus also did a great job at handling the difficulty setttings: Normal can be challenging, but you've got a fail-safe (the undo button) that can erase your mistakes and help you through the stages. Hard takes your crutch away, and most importantly, it changes up the block layouts on every stage to be harder and more complex. That is almost always a sign of a good developer - someone who actually takes the time to make some real changes for higher difficulties, rather than simply turning up some multipliers and calling it a day, because making a good game is actually important to them. The sense of urgency is also great, because you need to be fast in order to combo an entire stage while collecting all of the money, which is necessary if you want the gold medals. On top of that, the art is great, the OST is top notch as usual for Meguro, and there's also a story or something. Obelisk is still shit though.
5. Child of Eden - Rez with an actual scoring system.
6. Strania ~ The Stella Machina - Was really surprised by how much I liked this game. It has lots of weapons, and a scoring system that encourages you to use all of them evenly. Fun stage layouts, lagless online play, decent music, and it was a nice change of pace from the usual danmaku that every other shooter developer makes these days. Incredible value as well.
7. Bangai-O HD Missile Fury - It's like the DS version but good. The game has a ton of stages, so the level of quality is all over the place, but I find it easy to ignore the terrible stages because the great ones are so damn good. (The best stages are in Extreme mode, which unlocks after you complete the main game. Some of the puzzle stages were great as well)
8. Muchi Muchi Pork! & Pink Sweets - Wasn't sure where to place this one. Pork is a great game, but I think it falls apart a little once you try to go for the high-end scores because there's such an insane amount of boss milking, which is not fun in any game. If you ignore that, the game is incredibly fun. I was also surprised by how much I liked Pink Sweets 1.01, which is another game that has way too much boss milking, but it's still really fun to just play for survival. Sweets' relatively simple scoring system is also a breath of fresh air from Cave's usual complexities. Pork's matsuri version and Pink Sweets' arrange mode are also fun, so I'm sure I'll keep coming back to this because it has four enjoyable games on one disc.
9. Portal 2 - Starts a little slow, but it really picks up after a few hours and stay great until the finish. Gels added more variety to the game, letting them create more interesting puzzles, and the co-op stages are a lot of fun. The story was also enjoyable and pretty unobtrusive, aside from the few cutscenes here and there. Still need to finish the last set of co-op stages though.
10. Ghost Trick - Like Portal, it starts out a little slow, but the game becomes really damn good once it starts going full steam ahead. The gameplay is completely unique and fairly clever, the animation is incredible, the music is great, and it has one of the best stories this gen (up there with Nier and 999).
Serious Sam 3 and King of Fighters XIII will probably get onto my list though, so Portal and Ghost Trick are likely to get bumped.
Yakuza 4 was also great. Nice return to form for the series after the mediocre Yakuza 3.