Just played the PS3 version for about 2 hours, and I can say with confidence that it runs beautifully. Sure, it still has the lack of AA that us PS3 owners have come to expect, but the framerate seems to hold up quite well, even under heavy load.
I think the game's only issue with graphics is that it was released so closely to Uncharted 2.
On another note: wow, this game is going to be addicting like crack! I love how the RPG elements aren't strictly tied to the skill tree; for instance, you can also buy upgrades to increase ammo carrying capacity, and your proficiencies per weapon level up the more you use each weapon type.
Well done, Gearbox. Please continue to support this one into the future--we'll all be begging for level cap increases with a month!