I think we are riding the crest of a general uprising among the tribes against al Qaeda and its allies. This post describes a recent action in Iraq:

Fed up with violent and indiscriminate terror tactics, a group of more than 80 residents of the Adhamiyah district, on the east side of the Iraqi capital, banded together Sunday to oust suspected terrorists from a local mosque.

The uprising led to a string of events over the next 12 hours that ultimately resulted in the arrest of 44 suspected terrorists and the capture of three weapons caches.

The initial takeover of the Abu Hanifa Mosque occurred at about 2 p.m., apparently triggered by news that terrorists had murdered two relatives of a prominent local sheik. As the news spread, angry residents joined the sheik to storm the mosque, long believed to be a sanctuary for terrorists operating in the area, and ousted the suspected terrorists inside from the building.
It was after the uprising that the Iraqi Army and the US came in to take tips from the angry residents that led to finding even more weapons caches. I think it can be argued that what we are doing with the tribes is an attempt to manage and channel this anger against our common enemy. This grass roots action is not just limited to Sunni tribes. Several Shia tribes have already done the same thing. While the US military is adapting to this new grass roots reality, it appears the Iraqi government and many in our congress are being left behind by events.