If you haven't played it yet I STRONGLY suggest picking up Borderlands 2, even if you rent it. I still suggest it even if you don't like FPS games, hell I sure don't and I felt it was the best new game I've played since mid life of the PS2. If anything you can be like me and play ZERO and just stealth and melee everything to death like a BAUSS. It has one of the BEST villains I've seen in any game to date, Handsome Jack is just one of those guys you love to hate.
If you are in to using the PSN store you could pick up Castlevania: Harmony of Despair. It's like SOTN but multiplayer with many of the characters from all of the games. It can be quite a bit grindey though after a while.
Since the PS3 currently in my possession is actually "borrowed" from a friend I don't really own any games for it, save RockSmith, but I doubt you would want to play that or even have a real guitar for it. Plus the song selection is pretty terrible in my opinion, only a handful of gems.
Edit: Also, for the love of all that is good and just in the world do not buy Resident Evil 6, no matter what the price is.
Edited, May 9th 2013 5:02am by DamienSScott
FFXI: DamienSlvrblade Race: Elvaan Nation: San d'Oria Server: Sylph 2002-2007, Phoenix 2012
PUP WHM PLD MNK BLU BST SAM WAR BLM 99 BRD THF NIN DNC SMN RDM 50+
FFXIV: Damien Scott Race: Duskwight Elezen GC: Limsa Lominsa Server: Ultros
DoW GLA50 ACN50 PUG50 MAR 50 Rest30+
DoH/DoL All 40+