Not with a bang but with internal discontent. From Andrew Sullivan, both the Interior Ministry and a collection of Mullahs are express disapproval of the election.

On the Mullah’s

A committee of respected Ayatollahs (the spiritual fighters) have requested that the election be invalidated for the purpose of restoring the people’s trust in the Islamic Republic.  We request the people to stay calm and not to provoke the government agents.

From the Interior Ministry

As dedicated employees of the Interior Ministry, with experience in management and supervision of several elections such as the elections of Khamenei, Rafsanjani and Khatami, we announce that we fear the 10th presidential elections were not healthy

Protestors in the street can be made to look like counter-revolutionaries, but jailing Mullahs and Ministry officials cannot be mistaken for anything but tyranny. These statements are huge. They are how governments topple.