A generation ago, they were ousting the Shah. Could they now be ousting the mullahs?
Protests in Iran look serious. History provides examples of such movements yielding change (Philippines) and yielding repression (China). We note that the best success seems to come in countries with an ideological tradition that fosters democratic ideals (like Roman Catholic Christianity in the Philippines), as opposed to those where other ideologies hold sway (like "Red" China), though not always (it took the Red Army to dislodge Hitler from Catholic/Lutheran Germany). Dictators are dictators, but their country's traditions constrain them now and then.
The mullahs of Iran are not in an ideological context that fosters democracy. We expect violent repression. We'd prefer otherwise.
No one is Seldom Wrong about the future. So let's all stay tuned.