As was doubly confirmed this week, both by an official BBC news release and the above next DWM cover (out 10 March), there will be a six-minute special "Doctor Who" sketch for this year's Comic Relief which appears to feature two Amy Ponds. That should be part of the main TV show on Friday, 18th March. Though the main show has done several contributions to Children In Need over the years, most notably "Time Crash" in 2007 and the Eastenders crossover "Dimensions In Time" in 1993, I don't think anything has been done for Comic Relief. There was a Ronnie Corbett-as-a Slitheen skit last time with the "Sarah Jane Adventures" gang though. The canonicity of all of these will be hotly debated.
In what seems to be a general trend for this biennual charity, much of the activity happens in the runup, working as a slow-burn PR strategy. This year we also have the cast of the Inbetweeners travelling to Britain's rudest sounding places, a celebrity Kazoo orchestra for Radio 3, comedian flavour crisp contest (losers get body waxed), presenters/DJs from all the BBC radio stations attempting stand-up slots, and the traditional Comic Relief single, this time by boyband The Wanted (below). And much more as they say!