David Tennant has officially announced that he's leaving Doctor Who after the five shows in 2008-09. He made the announcement as part of an awards show in the UK, and has posted an interview on the official BBC Doctor Who site (where it's blocked to U.S. viewers, but easily found on YouTube.)
Tennant says it's time to move on, with head writer Russell Davies leaving at the end of 2009 as well; better to leave at the top of his game, before people start wondering when he's ever going to leave, etc. But there's also speculation that he wanted more than the BBC would offer--in money, time off and a Doctor Who feature film.
I guess either is possible. It seems weird that he would so severely shorten a season (after the upcoming Christmas show, four specials is all there will be in 2009) and then not come back for at least a final full season, especially with the chance to work with the new head writer, Steven Moffat (he did say that a conversation with Moffat about his plans for the 2010 season's stories almost got him to change his mind). But leaving when the team that brought him in dissolves also makes sense. I expect it's a little of both.
Now all of England wants to know who the new Doctor will be. Lots of actors have said they'd love to, a few said no thanks; several male actors mentioned--including the "frontrunner" in speculation for awhile--are black, and there's a movement to make the next Doctor a woman. Much has been made of the actor who plays an apparent Doctor double in the fiendishly titled Christmas special, "The Next Doctor," but that story was in production and perhaps even finished before Tennant actually decided to leave.
Those who are trying to figure out who the next Doctor will be--and most often focusing on young actors--might heed the words of Stephen Moffat, who will have a lot to say about who does become Who: "I don’t think young, dashing Doctors are right at all... He should be 40-plus and weird-looking — the kind of wacky grandfather kids know on sight to be secretly one of them."
Is he kidding? Would he get away with an older, weird-looking Doctor in 2010? Can they keep the selection a secret for a whole year? Or will that be enough time for Tennant (or the BBC) to reconsider?... Who knows?
Update: Absorbing this news, it occurs to me that Tennant may have dealt a fatal blow to the Doctor Who series, at least in the U.S. on the Sci-Fi Channel. Or if not fatal, then at least a stop in the momentum that was building up. First of all, because there are only five stories this coming year, each will have to be heavily promoted to get an audience (though they'll be front page news in the UK.) The habit of the weekly series will be broken, and then the new doctor will have to be heavily promoted. Will Sci-Fi and the BBC invest in all that? Some viewers just won't care enough to keep up, so the risks are considerable. Another Doctor as popular as Tennant--and it took him a couple of years to attain his current popularity--is not a given.