I have to agree with the readers comments to EA. The Iranian opposition, based on what has leaked out about the day's events, lacks on-the-ground leadership. The smartest thing they could do is head right back out onto the streets tomorrow, when the government isn't expecting mass demonstrations, but I'm not sure they have the organizational capacity right now to pull it off. To that extent, the large volume of arrests seems to have paid off for Ahmadi's administration.
The attack on Moussavi's wife Zahra has massive blowback potential though. As with Neda's martyrdom, that's the kind of thing that could provoke an emotional reaction in people who might not otherwise participate in a protest.
It's still a long road ahead.