Call of Duty is a very good port according to everyone but the multiplayer mode is a bit restricted afaik... (dont have the game unfortunately).
Perfect Dark Zero is a bit of a hit or miss. Id rent it first before buying it, some people love it (especially the multiplayer), some people hate it.
PGR3 is KICKASS in every sector. If you are even remotely interested in cars, buy the game. Its also a VERY good challenge.
Dead or Alive is very very good, eye candy wise, gameplay wise and multiplayer wise. Go get that as well.
Condemned has an excellent single player mode but no multiplayer and limited replayability...so i believe its just rental material (i did buy it though...).
Kameo is VERY good contraty to what youve heard. Excellent visuals, very good gameplay, and i belive it has online coop (havent tried it online though).
If i had to pick just 3 id go for
PGR3, DOA and COD/PDZ (ok thats 4

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