I heard they talked about this on the news so here :
Suns out : amare, diaw, barbosa
in : Sheed , Prince, Maxiell , pick
The suns get sheed who is a really good defender and be able to space the flour and be a good support to shaq, prince is what the suns need as a shut down defender and have good experience, maxiell come off the bench as an energy player. The piston take on diaw's bad contract and rebuild with a core of amare/stuckey.