Actually, the American Pit Bull Terrier rated higher than the Golden Retriever in the American Temperament Test Society's study:
http://www.atts.org/stats1.html
Also, they are used as certified therapy and SAR dogs. Two of the dogs from the Micheal Vick case were rehabilitated and became therapy dogs.
Pit Bulls, more specifically Staffordshire Terriers, I think, were considered excellent nanny/family dogs in the early 20th century. If you look at old cartoons and TV shows from back then, Pit Bulls show up quite often. The show "Our Gang", for example. Even the cartoon character Betty Boop had a Pit Bull.
As did Hellen Keller.
The Target mascot, Bullseye, is a Pit Bull, too.
Pit Bulls do have a tendency towards dog aggression, though, but they were NOT bred for human aggression. And even with other dogs, they are not completely bad, depends on the dog. Treader has been with Pit Bulls and not suffered anything from it.
Pit Bulls seem very common in my area and in general I've found them among the friendliest dogs to meet. The animal shelter seems to get a lot of them, too, and many of them do get put up for adoption--which requires passing a temperament test.
"“Pit Bulls have more bite pressure per square inch (PSI) than any
other breed.” This is absolutely false.
Tests that have been done comparing the bite pressure of several
breeds showed pressure PSI (per square inch) to be considerably lower
than some wild estimates that have been made. Testing has shown that
the domestic dog averages about 320 lbs of pressure per square inch.
Recently Dr. Brady Barr of National Geographic conducted a comparative
test between a Pit Bull, a Rottweiler, and a German Shepherd. The Pit
Bull had the LOWEST PSI OF THE THREE."
source:
http://www.realpitbull.com/myths.html
Look, I agree--big dogs can do more damage. But Pit Bulls aren't bad dogs, just the most common victims of bad ownership these days. Back in the 70s I hear it was the German Shepherds, then years later the Dobermans, etc.
You hear about them the most because they are useful in the dog fighting ring--they have that Terrier tenacity, which can be used in a good or bad way. (Just about any dog can be used in a bad way, really.)
Also because of the news media--face it, they are out there to make a buck and scary stories about scary-looking hellhounds sell. News journalists are not experts on identifying breeds and unfortunately Pit Bulls are easy to misidentify--LABS have been mistaken for them. Also, I've read that they often will not publish the story if the dog was definitely not a Pit Bull.
Not trying to fuel an argument, just I feel strongly about this, especially as the owner of a breed often considered untrustworthy and it hurts like heck when people tell me things like my German Shepherd is going to turn on me just because that's what they do (I've even had someone who never even met my dogs tell me to put Cookie down just for being a GSD when I told them about her)...I can only imagine how those Pit Bull owners must feel.
You're entitled to your own opinions and all...if you'd rather stay away from certain dogs or not own them, that's perfectly fine and your right.
This subject is one of the few things that will make me go off on a tantrum pretty much no matter who says it anymore, but what actually irks me is when people try to get Pit Bulls banned because of the hype, forcing others to give up their loyal pets because of mass misinformation. As long as someone doesn't want the breed banned, I'm good. xD
ETA:
As far as jaws locking, this is very easily debunked by a look at canine anatomy
It's beyond sad when you meet pitbull w/o a cage, young little girl is trying to pull him away from you, obviously very scared and struggling as pit is way stronger and she's trying to hold on the fence near to her in desperate attempt to stop up dog. And nope, I didnt make this up. It happened just few weeks ago. 
Just sayin, I wasn't there, but I guess it can happen.