Well, Powe, Davis, Moore (probably), Marbury and Pruitt will all be gone. House and Tony Allen may be gone as well. TA has another year on his deal, but he is certainly trade bait.
The only certain returnees are Garnett, Pierce, Perkins, Rondo and Ray Allen, and I expect Ray to be gone by June, 2010 at the latest.
On the plus side, I expect a number of good free agents to be available for the MLE or less. And we'll have a rasw young Turkish 7 footer in lieu of a first round draft pick. I wonder how long before Rivers ruins him also.