Nier! It's got an amazing story-line. I'm not into RPGs' normally but this one had me hooked. I beat the game 4 (four) times! If you've played it and enjoyed it, try out the DLC as well, it's fantastic.
Tropico 3 for the Xbox 360. Terrific city-building strategy sim. I wish Haemimont Games would have released Tropico 3's expansion via Xbox LIVE, but hopefully Tropico 4 will make up for the lack of post-release support.