According to NESN Sportsdesk, the Sox have traded SS prospect Kenny Perez and Kyle Bono to the D-Backs (it's them I think) and receive Cruz in return.
Not a bad pull. Cruz has struggled a bit this year, but he provides a Jay Payton type OF for the Sox, and with an OF of Ramirez/Damon/Nixon/Cruz/Kapler (or Stern), they have some of that hitting depth they have been without at times.