David Tennant could return for 2013

With the 50th anniversary of Doctor Who in 2013, it's been hinted at a multi-Doctor story. Although Christopher Eccleston has pretty much ruled out his return, David Tennant is enthusiastic about the idea of returning to Doctor Who.

Matt Smith and David Tennant in the TARDIS

“Not impossible forever, but no plans at the moment,” Tennant told Total Film. “People keep telling me that they’ve read online that I’m coming back – but believe me, if that happens I’ll be the first to tell everyone, I’ll be shouting about it very loudly,”
“I’m very proud of the show and I’m fully aware it casts a long shadow professionally, but I’m quite happy about that. It’s a shadow wearing a very cool, long coat!”