I never know what to think about Pit Bulls, really.... it's a tough thing.
I DO believe it's all in the way you raise them because my aunt has a Pit Bull who is the kindest, sweetest dog EVER and has never hurt a fly. He's 8 years old. However, I don't trust them. Perhaps that's a bit "racist" towards the breed lol but it's how I feel. Because if by chance they get pissed off, they can KILL you. And while most of the dogs I've seen that have been nippy have been the little dogs.... they can't do nearly as much damage.
If you happen to own a pit bull (or another breed of the like) you MUST be a major alpha leader, and I mean major, lol. They must know you're in charge.
I owned a German Shepherd as a kid growing up who was not trained properly and it was such an annoyance to have her. I loved her to death, she was MY girl, slept w/ me everynight but she was just not trained right. We could never trust her around guests or kids. You never knew what she was going to do. She did bite two people who tried to come into my room. And at the age of 3, she attacked a worker who came over to our house and he legally had to call Animal Control. She had to be put to sleep.
Devasting! But, nobody in this household trained her properly. I blame oursleves.