That is particularly good news. Ultimately it must come down to a workable political situation.
Getting rid of al-Qaeda in Iraq will at least make a political solution possible.
Creating a pro-American Sunni miltia around 200,000 men strong would go along way to forcing such a solution. Because, if Sadr and Hakim think they can piss on the Sunnis and give them nothing without a very high cost, that is exactly what they will do.
The Sunnis have decades of military experience the Shia are just starting to catch up.