Martha, Mickey returning?

Lots of buzz over the last week about a possible return (again) for Dr. Martha Jones, played by Freema Agyeman, in one of this year's upcoming specials. You can find the rumors here, here, here and here. Now, take that with the appropriately-sized grain of salt - I think there were a lot of rumors floating around in the last few months on purpose to keep fans from being completely unsurprised by the announcement of the 11th Doctor.