It's not really surprising that it's the twitter folks in Tehran and other cities who are involved. Nor is it surprising that they're proving instrumental in coordinating and maintaining contact. Every revolution in history, including the Chinese, depended on an educated middle class.
This is the moment when other groups might begin to join the twitter rebels, groups beginning to realize how the regime has screwed them over, too.
But the forces of repression could still prevail. If they do, the Iranian regime would be unstable. Elections were its legitimacy among the people. It is now widely perceived that the elections were falsified. It sounds like election officials, on orders from Khamenei, simply cooked up the numbers, because past electoral patterns were ignored, and native sons lost their provinces by ridiculous margins--including the main opposition candidate, Mousavi. It was blatant.
Why would the regime blatantly falsify? Is it desperate to stop social change? Ahmadinejad is its bulldog to keep change at bay.
Iran may have a very effective security apparatus, but if a regime has only that, given modern techniques of organizing, then the revolutionaries have a chance--if some of the security apparatus defects.
Is the resistance US-inspired? I doubt it. An Iranian tweet last night said Obama did well by not coming out in favor--US support would unite Iran's repressive and nationalist forces.
But the uprising could be a gift to Obama either way: nuclear negotiations could prove easier even if Ahmadinejad prevails; the regime will need legitimacy.
Change is possible in Iran; how about the US?