A good study...

This makes interesting reading. They try to add balance to the statistics used, and it's an Aussie study, not American, put together in a large hospital.

http://www.mja.com.au/public/issues/aug4/thompson/thompson.html

It doesn't paint us bull breeds in a great light, but nor does it allow for the standard of care given to individual animals... ie dangerous dogs usually have dick head owners.