They’re saying that Matt Smith has decided to move on already. Just imagine the Doctor regenerating into David Morrisey!
I really hate to see Matt Smith leave, he’s the best Doctor yet but there is something different about Oswin and she may lead to A change in Doctors.
She turned up in the first show of the last season as a Dalek and then she died in the Christmas special this year with the Doctor noticing that he middle name was Oswin.