This is order from timeline. Bottom is the oldest, top is the most recently played games. Never played anything close to this many games with one system. And even before I got the monthly game pass with Blockbuster I could say that...

Quantum of Solace
Tomb Raider: Underworld
Left 4 Dead
Guitar Hero III
Spider-Man: Web of Shadows
Madden NFL 06
NBA Live 06
Mirror's Edge
Collge Hoops 2k6
NCAA Football 07
NCAA March Madness 07
NBA 2K6
Call of Duty: World at War
Guitar Hero: Aerosmith
Gears of War 2
Fifa 09
Fallout 3
Fable II
Nascar 08
Prey
Far Cry 2
Brothers in Arms: HH
Tenchu Z
Fusion Frenzy 2
Guitar Hero World Tour
NBA LIVE 08
Lost: Via Domus
Gun
Saints Row 2
NBA LIVE 09
NHL 09
NFS Most Wanted
Cars
NBA 2K7
NHL 2K7
Tomb Raider: Legend
TimeShift
The Bigs
NBA LIVE 07
The Force Unleashed
Dead Rising
LEGO Star Wars II
Rayman Raving Rabbids
Too Human
TNA iMPACT!
NHL 2K9
Two Worlds
NHL 2K8
The Simpsons Game
Mercenaries 2
Smackdown vs. Raw 2007
Top Spin 2
Turning Point
Fight Night Round 3
F4: ROTSS
Jumper
Madden NFL 09
FIFA 07
NHL 08
Yaris
Call of Duty 4
X-Men The Official Game
MLB 2K6
Bejing 2008
Spider-Man FOF
Rock Band
TMNT
Assassins Creed
Harry Potter OOTP
Army of Two
Rainbow Six Vegas 2
Avatar
PES 2008
Blacksite
Madden NFL 08
The Bourne Conspiracy
Smackdown vs. Raw 2008
CSI: Hard Evidence
NHL 2K6
King Kong
Spider-man 3
Bully
GTA IV
GRAW 2
The Darkness
StrangleHold
Halo 3
MOH: Airborne
BF: Bad Company
Perfect Dark Zero
Call of Duty 3
Oblivion
Madden NFL 07
Undertow
The Orange Box
Mass Effect
Superman Returns
Bioshock
Call of Duty 2
NHL 07
Gears of War
Rainbow Six Vegas
G.R.A.W.
The Outfit