It is being discussed on many forums (for example on hacker news[0]). From today, internet users in Iran cannot make any SSL/TLS connection out of the country, basically they can only do http. On the tor list they are asking people to set up obfsproxys[1] to provide escape routes from this censorship. Anyone interested in helping can set up one of these proxies on their server/computer.
[0] http://news.ycombinator.com/item?id=3575029
[1] https://lists.torproject.org/pipermail/tor-talk/2012-February/023070.html