It's a good theory, but someone remarked that the Phase II screentest was already included as a DVD extra on some movie release before. I never actually saw it, but if it's been released before it can't be the big surprise, no?
Yeah it's really hard to say which way they're gonna go with that, but all the Ilia, Xon stuff, etc. has been seen so I hope its more than that.
But the average fan doesn't probably even know about Phase II and "The Child" and "Devil's Due" connections so it could very well be that.