I don't know about you guys, but Little Big Planet has me more excited than anything else.
It's a game where you create your own platformer by dropping objects in the world and psychically moving them using your little avatar dude. The game will come with a story mode/prepackaged levels but you can share your own custom levels online with everyone and link them together to create massive worlds.
The game uses real physics to determine weight and mass and you can create complex platforms out of them. For example, put a plank over a fulcrum and you create a makeshift teeter totter. Attach gears and a belt together, and you have your escalator or elevator. I'm not a big fan of penny arcade, but this comic summed up my feelings perfectly:
I'm pretty much buying a PS3 for that game. I'm a huge MGS fan, but MGS4 is just a bonus compared to LBP.
I'm also excited about Patapon for the PSP. It's like this quirky sidescrolling squad based action game and the art oozes style.