I train dogs for a living, and I have trained many, many pitbulls. 99% will lick you to death, and I have never been bitten by a pitbull in 16 years.
The problems I get them for are things like jumping up and jumping fences and pulling on the lead etc.
All dogs can bite, and I think you will find that pitbulls do not bite anymore then any other breed.
The problem is the owners (very small number) and not the breed, the thing with pitbulls is when they fight they tend to fight to the death, so are quite easy to turn into a fighting dog.
But lets be honest which animal is destroying the earth and kills more people then any dog could ever manage?