PS3.
If you want to play online, you'll be required to pay for the Xbox Live Gold subscription. With the PS3 you're not required to pay to use any online services other than subscription fees the services themselves might have.
Imo the exclusives on the PS3 are better. The 360 does have some outside of Halo, Gears, and Forza like Shadow Complex, Tales of Vesperia, Lost Odyssey, Left 4 Dead, etc, but nothing compared to the variety you can get on the PS3. Twisted Metal, White Knight Chronicles 2, Yakuza 3/4, Valkyria Chronicles, Demon's Souls, Tales of Graces/Xillia, Heavy Rain, Ico/SotC, Infamous, Uncharted, Little Big Planet, etc..







