I forgot asked how it was, I just got it two days ago. It rules! I've been playing the co-op campaign with my little brother and we completely sexually assault everything so far! We're only level 10 and it's so fucking fun! I can't wait for my cousin to get here so we can play 4 player co-op. I'm such a fucking nerd.
EDIT: Apparently Gearbox is already working on DLC (JUST PUT THE SHIT IN THE FUCKING GAME) and are talking about Borderlands 2.