Yeah, you have a point. Smith wants to film the episode live and he wants Billie Pipper to return, Pipper said "the ship sailed" for her time on the show, Tennant says that Pipper will not return, and is unsure he will, and I've heard no word from Mcgann recently. Although, I've seen designs for a sonic screwdriver he'd use if he came back. Moffat also said he'd change the costume bit. Also, for those of you who though a pre unearthly child 1st doctor would return for the episode, your both right and wrong! /http://www.huffingtonpost.com/2012/08/09/doctor-who-50th-anniversary-an-adventure-in-space-and-time_n_1760358.html ^^^Read more about it here!