Why are ps3 exclusives sellig so badly compared to xbox360?

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TOP 25 PS3 exclusive

Metal Gear Solid 4: Guns of the Patriots - 4.68 million
Resistance: Fall of Man - 3.68 million
Gran Turismo 5 Prologue - 3.67 million
MotorStorm - 3.52 million
LittleBigPlanet - 3.21 million
Uncharted 2: Among Thieves - 3.13 million
Uncharted: Drake's Fortune - 3.10 million
Killzone 2 - 2.25 million
Ratchet & Clank: Tools of Destruction - 1.91 million
Resistance 2 - 1.85 million
God of War III - 1.81 million
inFamous - 1.46 million
Heavenly Sword - 1.42 million
Heavy Rain - 1.12 million
SOCOM: U.S. Navy SEALs Confrontation - 1.00 million
Ratchet & Clank Future: A Crack in Time - 0.94 million
MotorStorm: Pacific Rift - 0.90 million
God of War Collection - 0.89 million
Valkyria Chronicles - 0.89 million
Hot Shots Golf: Out of Bounds - 0.85 million
Haze - 0.82 million
Naruto: Ultimate Ninja Storm - 0.82 million
Time Crisis 4 - 0.76 million
MAG: Massive Action Game - 0.75 million
Demon's Souls - 0.74 million

TOP 20 X360 exclusive

Halo 3 - 10.93 million
Gears of War - 6.04 million
Gears of War 2 - 5.66 million
Halo: ODST - 4.82 million
Forza 2 - 3.99 million
Fable 2 - 3.54 million
Left 4 Dead - 2.72 million
Left 4 Dead 2 -2.62 million
Call of Duty 2 - 2.47 million
Forza 3 - 2.41 million
Call of Duty 3 - 2.35 million
Tom Clancy's Ghost Recon Advanced Warfighter - 2.26 million
Mass Effect - 2.19 million
Saints Row - 2.03 million
PGR4 - Project Gotham Racing 4 - 1.93 million
Lost Planet: Extreme Condition - 1.82 million
Halo Wars - 1.81 million
Crackdown - 1.68 million
Mass Effect 2 - 1.66 million
Viva Panita - 1.62 million
Need for Speed: Most Wanted - 1.61 million
PGR3 - Project Gotham Racing 3 - 1.40 million
Grand Theft Auto: Episodes from Liberty City - 1.33 million
Perfect Dark Zero - 1.31 million
Dead or Alive 4 - 1.01 million

Exclusive games is clearly selling more on X360 than PS3 but lately PS3 had done lot better.