Joshua A. Tucker, an NYU professor and expert on the former Soviet Union, has written a piece on why the events in Iran will not turn into a full-fledged revolution:

As I watched events in Iran unfold at the end of last week, I couldn't help but note the similarities to the "Colored Revolutions" that swept through the post-communist region in the middle of this decade. Pre-election polls predicted a surprisingly competitive election in an erstwhile authoritarian country. Following the election, both sides claimed victory amid allegations of serious electoral fraud. Supporters of the opposition candidate took to the streets, and even had a color--green--lined up to give them the moniker of the "green revolution."

However, over the past three days, it has become apparent that Tehran is not turning into Kiev. While there are numerous important differences between Iran and the post-communist colored-revolution countries (Serbia, Georgia, Ukraine, and possibly Kyrgyzstan)--with the most notable being that ultimate executive power in Iran lies with the Supreme Leader, currently Ayatollah Ali Khamenei, who is not popularly elected--it does seem to me that the Iranian authorities may have learned a number of specific lessons from their less fortunate post-communist counterparts.

You can read the rest of the piece here.