This is a great deal for all sides involved if true.
The Kings get the interior presence they need and balance their inside position somewhat. Instead of one true center in Hawes and multiple PF's, they will now be 2 deep at center and May can move back to backup PF where he is more suited as opposed to starting center.
Also, they clear out the SF logjam. Casspi, when he returns, and Greene need minutes and it's tough to get as long as Nocioni is getting the pt there.
For Boston, they will now have the ideal backup for Pierce at the 3 as Walker and Giddens aren't the answer. Also, they get rid of the 2 guard logjam by letting Tony Allen go as it will now just be Daniels behind Ray Allen.
Philadelphia played their best ball when they went small and would like to shed Dalembert's contract anyways. Maybe moving Brand to C is a good idea in the short term plus they will have cap space in the future.