Fav Xbox: Fable 2
Fav PS3: Sly Cooper Thieves In Time
Nintendo: Mario Tennis Open

Fav xbox: Halo reach
Fav Wii: wii sports
Fav PS3: Uncharted 2, or Demon's Souls, or Journey I dunno I can't choose :/

Wii: Monster Hunter Tri

360: Gears of War 2

PS3: Uncharted 2

360: Halo 4
PS3: GT5
Wii: Xenoblade

One of my favorite RPGS of all-time. It's only going for $13.00 at GameStop, worth every penny.

PS3: Uncharted 2
360: Halo 4
Wii: The Last Story

PS3: God of War III - Easily the best game on the Playstation 3.
360: Gears of War - My favourite Xbox 360 console exclusive, Alan Wake is a close runner up.
Wii : Zelda: Twilight Princess - Pretty much the only Wii exclusive I've completed.

Wii: Super Mario galaxy
XBOX360: Forza 3
PS3: Journey

Playstation 3: God of War3 (Uncharted 2 close runner up)
Xbox360: The wired controller because it works great on my PC
Wii: The Legend of Zelda: Twillight Princess (Xenoblade Chronicles not close runner up)

360: Does Mass Effect 1 count? Over 50+ hours into that amazing story, even if the game had some flaws... Since it's on ps3 now I'll go with Halo Reach. Reach had the best atmosphere of any Halo game. 

PS3: So many.... But I'm going to go with Uncharted 2. An amazing story, presentation, gameplay, replayability (hunting that platnium), pretty good multiplayer, very memorable game. 

Wii: Super Smash Bros Brawl -  Oh gawd so many wondrous hours of fun