I think McElroy is the likely starter next year. Didn't they play Darrah over Jackson yesterday? If so, it looks like they are looking to keep his redshirt, so McElroy's still ahead at this point.
Barring injuries and bruised egos, I see 2008 as McElroy 1, Jackson 2, AJ redshirt, and then 2010 with AJ and Jackson in competition for 1. Darrah and Smelley could factor in as threes to preserve a redshirt for AJ next year.
RTR,
Tim