If its already been posted than deal with it
http://xbox360.ign.com/articles/916/916362p1.html
Heres the list if you don't wanna visit the site:
25. Ninja Gaiden II
24. Crackdown
23. Dirt
22. Battlefield: Bad Company
21. Virtua Fighter 5 Online
20. Eternal Sonota
19. Forza Motorsport 2
18. NHL 09
17. Guitar Hero II
16. Fight Night Round 3
15. Skate
14. Viva Pinata: Trouble in Paradise
13. Rainbow Six Vegas 2
12. Grid
11. Civilization Revolution
10. Dead Rising
9. Rock Band 2
8. Elder Scrolls IV: Oblivion
7. The Orange Box
6. Bioshock
5. Grand Theft Auto IV
4. Halo 3
3. Call of Duty 4
2. Gears of War
1. Mass Effect
Updated!