From Rooz Online:

Observers have estimated the size of these protests to be the largest since the unrest two years ago this month. Students from Allame-Tabatabai, Amir Kabir and Khaje Nasir universities too joined the protesting students from Tehran University.

Two years ago, if memory serves, is when Colin Powell pulled the plug of hope from the Iranian opposition by saying the United States didn’t want to get involved in an Iranian “family squabble.”