I'm very excited for Super Mario Galaxy 2, as there hasn't been a great 3D platformer in quite a while.
That being said, I've also been on a Western kick for the past couple of weeks, so Red Dead Redemption is high up on my list too. I'll wait for the reviews for that one, though.
EDIT: Oh man, I completely forgot about 3D Dot Heroes. I heard about it a while ago and it slipped my mind. It looks like a really cool game, and I'll definitely be checking into it.