Now, to choose one in each category.
FPS: BioShock
TPS: Gears of War
RPG: Oblivion
Strategy (on consoles): Civilization Revolution
Platformer: Ratchet and Clank Future: Tools of Destruction
Stealth Action: MGS4
Adventure: Uncharted: Drake's Fortune.
Hack and Slash: Nothing great until God of War III, but for now, DMC4.
Racing: Forza? Never played it.
Fighting: SSB Brawl