Moffat has said that he is writing the episode that explains who River is right now, not sure if that confirms or denies this rumour.
Steven Moffat has promised to reveal the true identity of River Song in the next series of Doctor Who.
The writer told New York Magazine that he is currently writing the episode where River Song's (Alex Kingston) true intentions towards The Doctor (Matt Smith) are made clear.
"Well, you will find out who she is and what's going on and how it all makes sense. And that will explain a number of things," he said. "I'm writing the episode right now where The Doctor finds out who she is. We're not just going to endlessly tease."
SourceThis excites me so much!! I love River, as you all know and I cant wait to see her back in action. I love the mystery surrounding her but I am hoping that once the Doctor knows her secret they can settle down into some normal travelling where she is just along for the ride as apposed to being a plot point.
I do however, fear that her reveal may be the end of her time on the show. I seek comfort in the fact that her diary was rammed full of adventures and so wouldnt be limited to a handful of stories and will still pop up even when there is no mystery around her