Kinda weird, but I'm thinking that Bell will have the better year than Moore. Moore will get his, but the fact that the defense will be concentrating on him will allow Bell to go racing down field for the long passes. I think Bell will have more yards and more TD's. Moore will dominate in the YAC category though.
To me a lot of it might depend on the way the OL holds up. If the OL gives whoever wins the QB job time to throw, that gives Bell a lot more opportunity. If the OL is a problem, as it has been the last few years, it gives Moore a lot more opportunity on quick passes, jet sweeps, and other plays that don't require as much from the OL up front.
But I think this might be a "pick your poison" type of offense. There are too many receiving weapons that you can't focus on all of them, and different opposing coaching staffs may not all pick the same ones. They might allow underneath stuff to Moore as long as they don't give Purdue to take the top off with Bell and Wright/Anderson. Or they may key on Moore and dare Purdue to actually complete longer passes to the outside receivers--and try to harass the QB at the same time with blitzes so he doesn't have the time to let those plays develop.
So I think you'll have some games where Rondale runs wild, and then the next week the DC will try to stop Rondale and Bell/Wright/Anderson burn them deep, leading to teams trying to contain them and Rondale getting his the following week...