Best Exclusives:
Halo 3
Gears of War 1 and 2
Fable 2
Crackdown
Mass Effect
Saints Row
Left 4 Dead
Metal gear Solid 4
Uncharted: Drakes Fortune
Ratchet and Clank: Future Tools of Destruction
Resistance 1 and 2
LittleBigPlanet
Warhawk
Motorstorm 1 and 2
Future:
(PS3)
Killzone 2
God of War 3
DC Universe: Online
Uncharted 2
Final Fantasy XIII(possible multi-plat)
Heavy Rain
Massive Action Game (256 man online)
Final Fantasy VII 2! (it could happen

)
Gran Turismo 5 (if you're into racing games)
inFamous
White Knight Chronicles (suppose to be the PS3's Fable)
(360)
Mass Effect 2(possible multi-plat)
Alan Wake
Star Ocean 4
Halo Wars
Plus you got your extras:
PS3:
Built in leet web browser, watch Youtube or anything
blu ray
huge media center
PSP-PS3 functions (if you want)
Home (not much yet, but maybe something cool in the future)
Playstation 1 and possibly 2 compatibility.
Playstation Store to buy movies ($14.99), just about ANY tv show. Any show that is currently on TV - Burn Notice/Prison Break/Family Guy and many old shows like scooby doo! And Batman and Robin. There is a crap load. ($1.99 an episode). Or rent movies. ($3.99)
And Playstation Store games and PS1 games.
Built in WiFi
360:
Run netflix through your account
Arcade
Theres more to the 360 probably, but I'm not all familiar with it so I can't say. The PS3 has suited me just fine with what I want. I stuck with the PS3 because of the exclusives like Ratchet and Clank, God of War, Jak and Daxter, Final Fantasy, Socom, and Metal Gear Solid from having the PS2 for a long time.