Statements have been made that he has a commitment to being in the 2009 specials.
But eventually, The Doctor will regenerate. (Because I refuse to see the show go away again)
So... now we start looking for potential actors.
Right now I have two front runners.
The first is Chiwetel Ejiofor
Which everyone on my reader list with the exception of s00j should easily recognize.
But I think my front runner is Alan Davies. Alan is best known in Britain as Jonathan Creek. He's got a very subdued humour which gives him a very Steven Wright quality. He delivers comedic moments in a manner that I often describe as "Joke Grenades" He also has a very Heath Ledger look about him which I think has that 'sex hook' that the Doctor always naturally carries. Despite his subdued nature he has an amazing range.
My only concern is that he looks TOO much like Tom Baker. And it may be viewed as treading backwards on the series.
Judge for yourself: