The Syrian Rebellion will be Defeated Before 11/06/2012
Prior to the rebellion, All reporting of Assad's behavior depict him as a relatively enlightened despot. Assad is not a bloodthirsty sadist; he is acting quite rationally:
Assad knows that, if he is going to end the rebellion by force, he has to do it before the U.S. presidential election. Obama has one issue left on which he has not entirely disillusioned his supporters--his role in ending the wars. He used a lot of political capital in Libya, and only survived because it was a quick, clean war in almost ideal circumstances for the U.S. military.
Intervention in Syria would not be such. Indeed, Assad is deliberately making war in such a way to make a quick, clean intervention difficult. He's not using his airpower at all. As part of a divide and conquer strategy, he's mixing his forces in with the rebels. He's moving his armor into the cities (which is not a very good place for armor), because it would then be protected from air strikes (the risk of friendly fire would be too great).
As a result, Obama is waiting. He's waiting until after the election, when either it's somebody else's problem, or he is no longer constrained by facing an election. Once the election is over, he can decide if he wants another messy war in the Middle East. And because Obama is waiting, everyone else is waiting. And while they're waiting, Assad's forces are carefully killing as many rebels as possible, but not so many that it would trigger an incident to which Obama would be forced to respond. If he wins before the November election, he will be invulnerable.
There's a military saying, "In war, the enemy gets a vote." In this case, it is almost literally true. The enemy, Assad, is voting by proxy in the U.S. election through the anti-war faction in the Democratic party.