Halo 3, Brothers In Arms, Battlefield: Bad Company, Rock Band , Rock Band 2, Call of Duty 2,Call of Duty 3, Call of Duty 4, Burnout Revenge, Burnout Paradise,Top Spin 2, Top Spin 3, Kameo, Dead Rising, Rock Star Table Tennis,1 Madden game, 1 NCAA College Football Game,Dead or Alive 4, NBA 2k6, NBA 2k7, NBA 2k8, Viva Pinata,Viva Pinata Trouble In paradise, Spinter Cell Double Agent, NBA Street Homecourt, G.R.A.W., G.R.A.W. 2, Lost Planet, Rainbow Six Vegas, Rainbow Six Vegas 2, Virtua Tennis 3, Oblivion, PGR3, PGR4, Street Fighter II, Far Cry, Crackdown, Forza Motorsports 2, The Darkness, Condemned, Bioshock, Stranglehold, Gears of War, Perfect Dark Zero, Turok, Mass Effect, Shadowrun, GTA IV, Army of Two, The Orange Box, Quake 4, Soul Calibur 4, Unreal Tournament 3, Saints Row ,Castle Crashers, and Skate.
56 games total. If my math is correct I have played 206 games for gamerscore alone. I came up with the list by taking my last generation gaming habbits into consideration. Not how good I think the games are now.
I will go one step further and list games I WOULD OF played if gamerscore didn't exist
Braid and Mega man IX
Only two off the top of my head. I would've played both games by now last generation.
More on the flip side of playing games strictly for gamerscore soon.