I doubt it - abuse through Tor is a legitimate problem. Wikipedia blocks editing from Tor for the same reason.
There are ideas for solving this though, and it would be cool to see more ideas, and more fleshing out of them. Mike Hearn has talked about having people make a bitcoin deposit for an account, and after so much time of legitimate use, the deposit is refunded. Before that, if it's used for abuse, the deposit is kept by the service. -tom
