The Orange Box. All the way.

call of duty modern warfare 2 ( nearly out) ,gears of war(everything in the series though the game is pretty short),i don't really recommend left 4 dead(it's just lyk an improved version of cs),gta 4 (ya, online , just dont be an immature sucker to online players)

COD4, gta4, fallout 3, street fighter 4, Gears of war 2.

Sequels ftw!

best option - wait for Halo 3 ODST. also wolfenstein is a nice game.

Mass Effect is the best Xbox 360 game I've played so far. Gta IV is also fun.

Halo3,Gears of war 1 and 2,CoD4,Rainbow6 vagas2

I suggest Fallout3, gta4, modern warfare,Prototype , left4dead is also fun(really fun, if you play it online)
Batman Arkham asylum just came out, it was also fun. and so is wolfenstein(2009)

Your Choice

Fight night round 4
If you like boxing.

crack
down


crackdown

sweet ass game, xbox exclusive.

Have to agree with this guy, prototype is the most fun I've had on a game in a while but for some people it can get repetitive. Also Fallout 3.