There's nothing scientific about the following; just a gut feeling, and my own intuition.
That leaves the battle for the No. 3 slot, and I'm guessing it's going to be John Parker Wilson.
D.J. Shockey is a fourth-year QB, and you don't see many rosters with four-year men holding clipboards. I think we (and the Falcons' coaching staff) have seen all there is to see with Shockley, and that by the end of this week, they'll name Wilson—an undrafted free agent rookie out of Alabama—as third-string QB.