The Twelfth Doctor was, of course, named in a BBC special on Sunday (actually aired live in the United States on BBC America) as Peter Capaldi.
The best piece of commentary about the announcement I've encountered so far is Robert Lloyd's piece over at Hero Complex.
Lloyd's acknowledgment of the odd mix of provincialism and global interest in the event is noteworthy. "As does James Bond," he writes, "'Doctor Who' posits a world in which the U.K. is still at the center of things. It’s where the aliens arrive, and the Earth is repeatedly saved." It seems worth pointing out that each hit the screen in the early 1960s, when the British Empire was going but not quite gone, and that just as Bond had his fiftieth anniversary on-screen last year, Dr. Who is having his this year.
Cultural superpowerdom seems to have a way of outlasting the other kinds.
Also noteworthy is Lloyd's reflection on the series' precedents for a figure such as Capaldi seems likely to be, which someone familiar solely with the Davies-Moffat era Who might not guess at.
Watching Doctor Who at Fifty
My Posts on James Bond