1. Wii Sports: I don't care if it's "casual" or whatever, this is the game driving Wii sales and it provides an experience truly like nothing before it.
2. Portal: The FPS genre finally sheds the muscles and blood and grows a brain. Brilliant gameplay and brilliant writing.
3. Mario Galaxy: Not much truly unique here, but it's one of the most polished and well designed platformers in history. Everything about it has been tuned to near perfection.