Children in Need is currently airing on BBC. This is a time of year that typically features a one off Doctor Who. It was a Children In Need special that had Joanna Lumley as a female Doctor.
This clip, uploaded to YouTube by the Beeb, has Matt Smith and Jenna-Louise Coleman introduce a trailer for the Christmas Special. No clues as to who JLC will be playing; Oswin Oswald as seen on Asylyum of the Daleks or someone else such as Clara Oswin.
The clip shows a sulky Doctor, clearly brooding over the loss of the Ponds, while the three from Demon’s Run try and get him interested. Despite the lack of Companion clue the clip really seems to confirm the time period in which we expect to encounter Jenna-Louise Coleman again.