Stealing the idea from Twesterm:
Uncharted -- very good refreshment of Tomb Raider idea with a bit more shooting.
LBP -- interesting unusual platformer , altrough all the comunity stuff is way too exagerrated, real fun is in creators levels when played with family or friends locally.
Killzone 2 -- generic shooter title
Wipeout HD -- probably best existing arcade racer, requires mad skills and tons of time but satisfaction from betting some of the challanges there is great. Also best ever value for download only game ever.
Flower -- unusual experience, worth checking as one of more unique "games" in existence
MGS4 -- this is game i'd love to see how someone plays it all but i feel absolutely no need to play it on my own
Resistance: Fall of Man -- classic FPS, usually can be found dirt cheap so worth checking
Resistsance 2 -- I only checked multi , which was good (becouse it reminded me of counter strike), imho R1&R2 can be skipped without losing much.
Ratchet and Clank -- I hate 3D platformers
Eye of Judgment -- i find it pointless, they could just as well made cards fully virtual. If i wanted CCG on screen I'd go for magic online.
Motorstorm -- boring when compared to Wipeout
Valkyria Chronicles -- holy grail of SRPG lovers, if you don't like genre you probably won't understand why people love it so much
Folklore -- Try demo. It's extremly interesting and great game but it might be not your cup of tea.
Heavenly Sword -- Gow clone, but much more enjoyable imho. Demo is pretty weak compared to full. Also it's very short so get it only if you can buy
PROUD MEMBER OF THE PSP RPG FAN CLUB