Exclusives-only: Flower, then yeah I guess God of War III.
Anything-goes: Flower, then Rock Band 2.
But yeah there's a buttload of stuff I'd take over Valkyria/Uncharted: Bayonetta, Heavy Rain, Demon's Souls, BioShock, Batman: Arkham Asylum, Assassin's Creed II, and probably stuff I haven't gotten to yet like Darksiders and Just Cause 2.
They're still good games though! There's lots of great stuff to play on PS3 these days! (finally)