You came to the right place
-Uncharted: Drakes Fortune and Uncharted 2: Among Thieves <-- #1 series on the PS3. If you have a PS3, then you must have these two games. Uncharted 3 comes out in November.
-God of War Collection and God of War 3 -- Kratos is a bad ass.
-Killzone 2 (Killzone 3 comes out on the 22nd)-- Pretty good shooter, Killzone 3 will blow 2 way out of the water though
-Resistance: Fall of Man, Resistance 2, Resistance 3-- another nice sci-fi shooter.
-LittleBig Planet 2-- really fun and addictive, you can create levels and play other peoples levels. While LBP1 was fun, this one trumps it big time.
-MLB The Show-- best baseball game on the market
-InFamous-- Really fun, original, "super hero" game. electricity is your super power, and its an open world game.
-Metal Gear Solid 4-- I'd only recommend this if you've played the first three. Otherwise it might not make much sense to you. But still, one of the top 3 best games on the system.
-If you enjoy JRPG's, then Valkyria Chronicles is the best choice.
-For hardest game of all time- go with Demons Souls. ridiculous hack n slash game.
-Heavy Rain
-Gran Turismo 5
-Motorstorm
-MMO Shooter, MAG
For future titles to look forward to-
-Rockstar is apparently making a huge game for the PS3 called Agent. It's Rockstar, so you know it'll be good. Who knows if it'll stay exclusive though, LA Noire used to be.
-Twisted Metal
-SOCOM 4
That's all for now. Too tired.