Yea, i'm playing it too. Loving it, but Borderlands and Modern Warfare 2 are eating up my time.
Tomorrow, Borderlands: Zombies gets released for download, so i know i'll be sucked into playing that some more.
I started it on PS3 last night, and I'm about 3.5 hours in... Combat is a little goofy, and it can be a little glitchy with the graphics, but I'm looking forward to finishing it. It definitely seems like it will have good re-playability. The reviews make it seem like the PC version is best choice, but I'd rather kick back with a controler than sit at a KBM.