Chatroulette is an interesting concept. On the plus side, it reliably provides people to talk to (especially if you're a hot babe), and leads to some actual conversations. On the downside, it has too many (literal) wankers, and feels lonely and disconnected while at the same time feeling like it's always just about to give you some real social interaction in the same way IRC does. I don't feel myself getting sucked in, but then I stopped feeling the allure of IRC a few years ago.
What the world needs is a service which is to chatroulette what yammer is to twitter - the same service, but only for people who have accounts on the same domain. That would allow it to be un-anonymized, since it could display the user's login, and solve the wankers problem, because HR and a lack of anonymity takes care of that. For companies above some size, it would be a great way for people to get the sort of random interaction with coworkers that they normally do in the office while working remotely. It would also probably have an easy upsell to an expensive premium service for any company which started using it a lot, even if they didn't mean to.