My $0.02:
Personally, I don't like being around Pittbulls (or some other breeds including Rottweilers, Dobermanns, Cane Corsos, Akitas, Neapolitan Mastiffs and German Sheperds. These are the first breeds that come to my mind) at all.
Why? I know that they are capable of inflicting severe damage and have done so in the past (no one can deny it, just google it. PS: I was attacked by a German Sheperd, my mother and sister by a Neapolitan Mastiff).
I certainly know that how a dog was raised is a major, major factor in how said dog will interact with a person. However, I still just don't trust these dogs at 100% (even worse the scenario of meeting an unsupervised dog out on the loose: who knows who raised it, how it was raised and what are its intentions...) and therefore I just prefer to err on the side of caution and just avoid them at all cost.
And that's my right as a citizen of this free nation. Now I understand that people who love these type of breeds and are responsible owners won't be pleased by someone like me completely rejecting the breed of their beloved pooch but that's simply my choice. At the end, I respect their choice of breed and they must respect mine (and please keep your dog away from me, thanks!).