Fareed Zakaria made some key insightful points in an interview about the revolution - what it means and where it is going:
Key point on Khamenei's loss of legitimacy:
When the supreme leader, Ayatollah Ali Khamenei, declared the election of Mahmoud Ahmadinejad a "divine assessment," he was indicating it was divinely sanctioned. But no one bought it. He was forced to accept the need for an inquiry into the election. The Guardian Council, Iran's supreme constitutional body, met with the candidates and promised to investigate and perhaps recount some votes. Khamenei has subsequently hardened his position but that is now irrelevant. Something very important has been laid bare in Iran today --- legitimacy does not flow from divine authority but from popular support.
Another point from Zakaria, that this is probably just the beginning of the end:
One of the first things that strikes me is we are watching the fall of Islamic theocracy.
I don't mean the Iranian regime will fall soon. It may -- I certainly hope it will -- but repressive regimes can stick around for a long time. I mean that this is the end of the ideology that lay at the basis of the Iranian regime. The regime's founder, Ayatollah Ruhollah Khomeini, laid out his special interpretation of political Islam in a series of lectures in 1970. In this interpretation of Shia Islam, Islamic jurists had divinely ordained powers to rule as guardians of the society, supreme arbiters not only on matters of morality but politics as well. When Khomeini established the Islamic Republic of Iran, this idea was at its heart. Last week, that ideology suffered a fatal wound.