From what Frank said in a recent interview in an Omaha paper, I think the QB job is truly open right now. I think more so than in previous years when you could get a good sense of who had the upper hand, or at least where the "smart money" was. In this case, I'd guess that it's about 50/50.
Of course the head coach is going to say there is a quarterback position battle one week into camp - he wants them to push each other and not have one of them let up because he knows he has the starting job locked up. Coaches know who has the ability to carry the offense and who has flashes of the ability to carry the offense by this point.
With the history of this coaching staff, it would not surprise me if they never truly or officially announce a starting QB before game #1.
Boo runs the offense and Bates is your Tebow back.
Leak/Tebow deal.