Quarterbacks on the roster next year, assuming Mallett boogies, are as follows...
Steven Threet
David Cone
Nick Sheridan
Obviously all of the above are old-system quarterbacks. Threet is the Georgia Tech transfer, and Cone and Sheridan have not seen game action save a couple token handoffs against Notre Dame. They didn't fumble, which is nice. Cone appears to be marvelously useful as a clipboard stand. None of these will strike fear into Jim Tressel, nor even, I suspect, Tim Brewster.
However, RR did not get where he is today by being stupid, or by sitting back and going "damn, no recruits." I suspect there will be a few recruits that didn't hear from Carr but will get a phone call or two from RR's gang. Obviously Pryor is a candidate. The aforementioned MarQueis Gray would indeed be a natural choice. Some other names would be Kody Spano, Domonick Britt, or Tommy Reamon. Oh hey - guess what school was recruiting Britt before he committed to (and then backed out on) Cincy? So there's a bit of a prior relationship there.
I would be willing to bet copious amounts of money that one of those names - Pryor, Gray, Spano, Britt, or Reamon - will be on the back of a maize-and-blue uniform next year. Any one of them would be more likely to start than the current corps of candidates.