IMO, there will be extensive use of air power, but also a very quick initial ground campaign as well to at least secure the waterways and oil fields in the south (to prevent him torching the fields as in 91), and the route to Jordan and the SCUD launch sites to the west (to keep Israel from coming under fire). This initial campaign completely isolates his forces and Bagdad becomes a city under siege.
There will then be LOTS of SOF activities in facilities located all over the country looking for WMD and terrorist activities in both areas he did and did not exercise control over.
In and around Bagdad, precision airstrikes, SOF, and bunker busters will continue to take out his resisting forces, palaces, govt buildings, bunkers, command structures, etc, until he is either dropped in one of the attacks or someone puts a bullet in his head for him. And yes, eventually we (and some Northern Alliance equivalent) roll downtown, but only after the Iraqis would be ashamed to ever admit to wearing a uniform for Saddam.