After a frankly bizarre "announcement" programme hosted by Zoe Ball on BBC1, the identity of the actor who will replace Matt Smith as the Doctor has been revealed as Peter Capaldi. (For a glimpse of how ridiculous the show was - at one point they randomly interviewed Bruno Tonioli off Strictly - check out Stuart Heritage's Guardian live blog.)
Capaldi revealed to Ball that he is a lifelong fan of the show - he even wrote to the Radio Times to request more coverage of the show when he was 15 years old. Perhaps most famous for his performance as the steely, sweary spin-doctor Malcolm Tucker in The Thick of It, Capaldi has actually already appeared on Doctor Who during David Tennant's stint as the Doctor playing a Roman marble merchant called Caecilius in the 2008 episode "The Fires of Pompeii" (incidentally also Karen Gillan's first appearance on the show as a soothsayer - she was later cast as companion Amy). He was also in the Torchwood: Children of Earth series as government minister John Frobisher.
In an interview during the annoucement show, outgoing Doctor Matt Smith explained that Capaldi came up to him on the street after his first episode had aired, and gave him some much-need reassurance that his performance was good.