I saw it last night. Went in with low expectations, in light of the reviews. However, I did enjoy the movie. It wasn't as good as the first one but wasn't the mess I'd feared. The script was wittier than I'd been led to believe and the action scenes were excellent.
I was surprised by the escalation of the violence but from reading this thread, I see that this came from the comic (the first one was pretty violent too, come to think of it).
I'd give it 7/10.