Chatroulette suffers from the exact same problem that ww.com suffers from, which is that it takes only a very small percentage of 'jerks' (how appropriate) to spoil it for the rest. On ww.com I've managed to somewhat mitigate the problem by making labeling of your content mandatory.
I've spent an awful lot of time on trying to automate the detection of inappropriate content but there are many reasons why that is a lot harder than it seems.
A chatroulette based on a 'real-names' log-in procedure that would then connect users anonymously would be one possible way to combat the problem.