The BBC had this to say about Matt Smith's departure...
The last time showrunner Steven Moffat was asked how long incumbent Doctor Matt Smith would remain in the role, he snapped back with a cheerily brisk "Forever. For the rest of time". There's the slightest chance you know, that he wasn't telling the truth...
Of course he wasn't. If there's one thing more certain than death, taxes, and repetition of the phrase "Doctor Who?" in the new episodes, it's that Matt Smith won't be the Doctor forever. The Sun, amongst others, is keen for us to think that his departure will come sooner rather than later, namely, after the 2013 Christmas special. The newspaper ran a story suggesting that "Insiders say the festive special will be Matt's last outing as The Doctor", citing Smith's ambition to break into Hollywood as his reason for bowing out after a four year stint.
The BBC was quick to respond to the story, and had this to say:
“Sorry folks but even we don’t know what’s going to happen at Christmas. It’s not been written yet! But Matt loves the show and is to start filming the unmissable 50th anniversary, and the new series starting on Easter Saturday.”
It's not exactly a denial, and neither was Smith's answer to the question posed by Jonathan Ross last week, "I am very happy doing it. I do the anniversary special, then the Christmas special. At the moment it’s 2013 and we will see what 2014 holds.”
If Matt Smith does indeed vacate the role, I for one will be very pleased. He's a very good actor, but I've hated his portrayal of the good Doctor, way too many cringe-worthy comedic moment for my liking, and lets be honest he had a tough act to follow, stepping in to David Tennants shoes. When you spend a whole episode frowning, you know something is wrong, which I do every episode of Doctor Who.
So who would make a great Doctor Who? Bennedict Cumberbatch would make a great Doctor Who, but he's turned down the role before, and he's now cracked Hollywood, he's in the new Star Trek movie.