The QB who will be playing (Zwick) started the first 6 games of the season. He is not as mobile as Smith, but is a better passer. As a die-hard Buckeye fan, I think the key is the play calling. I think that when Zwick was the starter, Tressell's play calling was more conservative. It was so conservative that there was a lot of discussion in Columbus about how he needed to hire an Offensive Coordinator to do the play calling because he had become way too conservative. Since then, Tressell has opened things up a little bit and the offense has benefitted.
The big concern for tonight's game is the Buckeye rushing attack. If Lydell Ross gets most of the carries, Oh St. will probably have less than 100 yards on the game and it will be up to Zwick to carry the load. If Pittman is getting the carries (he averages over 5 ypr) then this should open the passing game up for Zwick. I think it boils down to play calling and Tressell has shown in that he is not afraid to open it up in big games (Michigan, Miami and K-State).
If I am not mistaken, Zwick was Mr. Football in the state of Ohio. He got a full ride to Ohio State - he doesn't suck. Also, Teddy Ginn did not emerge as an offensive threat until Smith was starting. You can expected Ginn and Santonio Holmes to make things happen as long as Zwick can deliver.