Most are predicting a division of Iraq into three nations. This because that seems to be the will of the UIA (The shiite religious party which won a plurality in the recent elections). They want to live under the mullahs. The rest of Iraq will never go along with that. So the UIA looks determined to take their part of Iraq and go their own way rather than compromise and hold Iraq together.

Where this leaves American troops is completely unclear. My guess is we will end up supporting the Kurds regaining Kirkut and then setting up military bases in the new independent Kurdish state in northern Iraq. Shia southern Iraq will become closely aligned with Iran for a decade or so until the people finally get their heads where the sun shines and give democracy another try. Sunni Iraq could become either radical or democratic. Both forces are powerful there at the moment.

There is a small chance Iraq will form a unity government still but only if the UIA does an about face or splits up internally.