This week's edition of British satirical magazine "Private Eye" claims that the planned air date for the next season of Doctor Who is August 2014.  This ties in with the Radio Times announcement that filming for the next season starts in autumn, so it's rather probable. If they're still casting a new Doctor right now, it's quite that the pre-filming process could take until then.
They tie this in with a longer article about the various public relation mishaps the show has suffered recently; the DVD finale releases that American fans received a week early, John Hurt giving his local paper the scoop about his appearance on the program (also a week early), and the slightly haphazard way that Matt Smith's announcement was made (Ian Levine's Twitter was just one of the "fans and the Internet" sources to have the news before the BBC officially released it). How much of this you care to interpret in the same fashion as "Private Eye" is up for debate, but on the plus side, if it's true that means we get a full slate of episodes next year and not another half-season.

"Private Eye" has previously published some controversial reports on the show; the BBC went out of its way to deny claims that the 2012 series would consist only of four specials when the magazine reported as much in June 2011 (as it turned out, they were only off by two episodes, despite Steven Moffat's Twitter on the subject). Their report on Caroline Skinner's leaving has not been commented upon by any of the involved parties, understandably.

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