This is such a mixed subject... in my opinion I truly think when a dog acts out and attacks it can be both the owners fault and the dogs fault as well. You have to take nto consideration if the dog was provoked as well.
From my experience with pit bulls we have never had any issues with them being aggressive. My brother only has pits and they are babies!! So sweet and kind and actually love being with my children.
My parents now have a pit and he is the exact same way. Play with the kids and just loves on everyone. Has never bitten or been aggressive towards anyone. I think sadly, pit bulls have gotten a very bad wrap. When you hear such terrible things in the news people tend to think it is just the breed and all are bad and that is simply not the case.