The year of the sequel,

1. Dead Space 2
2. Portal 2
3. Mass Effect 2 (included because I waited for it to be released on ps3)
4. My number 4 consists of the collection of arcade games that were great this year:

Torchlight
Stacking
Ilomilo
Bastion
Guardian Heroes
From Dust
Outland
Fruit Ninja Kinect

Actually make those 4. through 10. with an honorable mention to Fruit Ninja cause that's all I've played.