recommend me games that would keep me busy until august, when good games release

with a lot of good games that were expected to release during summer, like mass effect and bioshock (i know those dates weren't official, but it had my hopes up really high). i need a game that would keep my busy for awhile during the summer. only high quaility game that is on my radar is forza motorsport 2. can you guys recommend me any games that would keep my busy for the summer? forza motorsport 2? guitar hero 2? oblivion?

games i have are: gears of war, rainbow six: vegas, nba 2k7, GRAW, ncaa football 07, halo 2, gta 3, san andreas, 007:nightfire, and kotor. even thought i mentioned original xbox games in my collection, but recommend me only xbox 360 games. your help would be apprecicated:)

One of my favorites, that kept me busy beating the entire game, for almost two months is Hitman: Blood Money.gatsbythepig

Hehehe, you've recommended the game to like 30 people in the past couple of days!! LOL. I know it's awesome, I went back to it this morning to finish getting a shiny 1000 on it.

Oblivion, definately.

 Lost Planet is long with its online play.

I say oblivion.