Xbox only games:
Halo
Halo 2
halo 3
halo 3 odst
halo reach
halo wars
Project Gotham Racing 2
MechAssault
Sega GT 2002/ Jetset Radio Future
Unreal Championship
Unreal Championship 2
Forza Motorsport 3
F.E.A.R. Files
Fable II
Fable II Pub Games
FIFA 06 Road to FIFA World Cup
Forza Motorsport 2
Dance Central
Dance Dance Revolution Universe
Dance Dance Revolution Universe 2
Dance Dance Revolution Universe 3
Dance Masters
Dancing Stage Universe
Dancing Stage Universe 2
Dash of Destruction
Dead or Alive 4
Dead or Alive Xtreme 2
Dead or Alive: Code Chronos
Dead Rising
Demons of Mercy
Diario: Rebirth Moon Legend
The Dishwasher: Dead Samurai
The Dishwasher: Vampire Smile
Don King Presents: Prizefighter
Double D Dodgeball
Dream Club
Capcom Platinum Hits Triple Pack
Carcassonne (video game)
Castlevania: Harmony of Despair
Catan
Chaos;Head Love Chu Chu!
Chromehounds
Cloning Clyde
Coffeetime Crosswords
Comic Jumper: The Adventures of Captain Smiley
Commanders: Attack of the Genos
The Conveni 200X
Crackdown
Crackdown 2
Crazy Mouse
Culdcept Saga
Banjo-Kazooie: Nuts & Bolts
Bankshot Billiards 2
Basement Pool
Battlezone (2008 video game)
Beat'n Groovy
Beautiful Katamari
Biology Battle
Blue Dragon
Bomberman Live
Bomberman: Act Zero
Boom Boom Rocket
Bubble Bobble Neo!
Bullet Witch
Absolute: Blazing Infinity
Ace Combat 6: Fires of Liberation
Aegis Wing
Alan Wake
America's Army: True Soldiers
Amped 3
Apocalypse: Desire Next
Aqua (video game)
AquaZone: Life Simulator
Assault Heroes 2
Axiom: Overdrive
Galaga Legions
Gears of War 2
Gears of War 3
Geometry Wars: Retro Evolved 2
Geometry Wars: Waves
Geon: Emotions
Gin Rummy (Xbox Live Arcade)
Go! Go! Break Steady
Golf: Tee It Up!
Guilty Gear 2: Overture
Kinect Joy Ride
Kameo: Elements of Power
Kengo: Legend of the 9
Kinect Adventures
Kinect Sports
Kinectimals
Kingdom Under Fire: Circle of Doom
Konami Classics
Lazy Raiders
Limbo (video game)
Lips (video game)
Lips: Canta en Español
Lips: Number One Hits
Lips: Party Classics
Little Gamers (video game)
Lost Cities (video game)
Lost Odyssey
Love Football
M
MagnaCarta II
Mamoru-kun wa Norowarete Shimatta
Marble Blast Ultra
Memories Off: Yubikiri no Kioku
Milo and Kate
MLB Stickball
Mobile Ops: The One Year War
Monday Night Combat
MotoGP '06
Mr. Driller Online
Mushihime-sama Futari
Mutant Storm Empire
Mutant Storm Reloaded
Naruto: Rise of a Ninja
Naruto: The Broken Bond
Ninety-Nine Nights
Ninety-Nine Nights II
Ninja Gaiden II (2008 video game)
Novadrome
Ok i think i listed enough 360 games now for some ps3:
The Last Guardian
The Last Guy
Last Rebellion
Linger in Shadows
LittleBigPlanet
LittleBigPlanet 2
LocoRoco Cocoreccho
Metal Gear Online
Metal Gear Solid 4: Guns of the Patriots
Misato Katsuragi's Reporting Plan
Mist of Chaos
Miyasato Miyoshi Kyoudai Naizou: Sega Golf Club
Mobile Suit Gundam: Crossfire
ModNation Racers
Monster Madness: Grave Danger
MotorStorm
MotorStorm: Apocalypse
MotorStorm: Pacific Rift
Mushroom Wars
Sports Champions
Start the Party
Super Rub 'a' Dub
Supercar Challenge
There are more but i cant be bothered listing in total there are about 183 PS3 only games, and there is about 209 total that are xbox only games.