1. The Gunstringer
The proof (besides Dance Central) that you can have a "real" game on the Kinect that works and is fun.
2. Gears of War 3
A satisfying ending to the Gears trilogy. Oh, Cole Train as a playable character!
3. L.A. Noire
Not perfect by any means but wow, the expansive world and expressive faces an adventure game that I finally enjoyed.