A few PSN games I would recommend you to have in your library:
Spelunky
Kickbeat
Lone Survivor
Velocity Ultra(GET IT)
Hotline Miami
Dokuro
Oh and Virtua Tennis 4 is a top notch sport game and if you don't already have it on PS3, Sonic & all-stars Racing Transformed is great.(coming to PS+ in December if you have the service)
http://gamrconnect.vgchartz.com/thread.php?id=130023&page=1# Official Playstation Vita Thread! Come in and join!!!







