Let me know if you had a different voting format in mind.
Best Xbox 360 Game - Halo 3
Best FPS/TPS - Halo 3
Best Racer - GRID
Best Action Game - Ninja Gaiden 2
Best Adventure - Castlevania SotN
Best RPG (J and W) - MAss Effect
Best RTS/Strategy Game - Halo Wars when it comes out :)
Best "Other" Game - Viva Pinata
Best Xbox 360 (Console) Exclusive - Halo 3
Best MultiPlatform Game - GTA4
You forgot
Best fighter - Street fighter 2 Turbo (Online)
Best Xbox Live Arcade - Castlevania SoTN
*EDIT - changed my adventure vote