Yep.
My pet Bengal Tiger is very sweet. He plays so nice with my 2-year old niece.

While Pits aren't the most aggressive breed, the problem lies in their "ability" to do a lot of damage.
I've met a lot of very sweet and gentle pits.
But once they get aggressive and get a hold of something, they aren't letting go.
Like everything else in life, stereotypes are there for a reason.