Oops, John Hurt has just confirmed that he is indeed playing The Doctor.
Time to get out your Tippex and start replacing all those references to the 9th, 10th and 11th Doctors you might have in books or on toys.
http://www.edp24.co.uk/news/john_hurt_launches_sheringham_little_theatre_cinema_campaign_1_2184494
Actually, this is the quote:
That article said:Mr Hurt, who lives near Cromer, earlier told the EDP he had just finished shooting a Dr Who 3D special in which he plays “part of the Doctor” in a “kind of trinity” which includes David Tennant.
I bolded the words "part of the Doctor" to highlight the ambiguity. He could be something like "The Watcher" from 4-5's transition or the Valeyard.