Marc Lynch sizes up yesterday's events:
[T]he prospects for regime change have seemed to me less likely over time rather than more likely. During those chaotic first days after the "election" fiasco, there may have been the chance for a massive cascade to change things before the regime could rally itself. But it survived that (and would have, probably even more easily, [had] the Obama administration publicly taken a position). Since then, it has systematically repressed and divided the opposition, harrassed its leadership and members, and taken steps to shore up its instruments of control. The internet may or may not have played a decisive role in fueling the Green Movement, but either way the regime is now prepared to shut it down when necessary. The Shi'a tradition of commemorations and major national anniversaries do offer focal points for organization and mobilization, but it also tells the regime exactly where and when to expect protest activity. In short, I fully believe that the Iranian regime is more unpopular and less legitimate than ever before -- but just don't see it as especially vulnerable at the moment.