Who's going to replace Steven Moffat as Doctor Who showrunner?

Steven Moffat's been in charge of Doctor Who's storytelling since 2010, and he's probably nearing the end of his tenure. So everybody's wondering who could take over this insanely demanding job, when the show regenerates next time. Let's break down seven prospects, in order of most likely to least likely. » 1/17/14 12:45pm 1/17/14 12:45pm