NIAC highlights a comment made by one of Mackey's readers:
Qom is in many ways the heart of the last Revolution (how it ended up anyway) and its aftermath. Until now, the regime has tried very very hard to isolate Qom from the protest movement. The security presence there has always been reported as very high to prevent any protests. [...] With today’s protests in Qom, and the clergy’s close-up view of it (perhaps for the first time for some of them) it will be interesting to see what the Qom clergy does in the days and weeks to come.
NIAC adds:
The next day to watch is Sunday, when two major days of mourning coincide: the day of mourning for Ayatollah Montazeri (the seventh day after his death) and the religious holiday of Ashura, which marks the martyrdom of the Imam Hossein.