Looks really weird... also, not stable 30fps.
Facts:
-Game IS very unoptimized, you WILL get framerate drops no matter your setup. This is from over 20 people I've talked to about it, all with mid-top setups. All the same types of drops present on the consoles. Just lessened, usually I've heard it gets as low as 17fps on a GTX260. Also heard input lag complaints.
-Keyboard+mouse controls are terrible. Use a controller. This might not apply to everybody but everybody I've spoken to says they suck.
-Same bugs and glitches as the consoles.
So overall, nothing that bad, but that's what I've heard so far. Steam version can't unlock soon enough, tired of waiting.