I would say darkhorses, plural, because I expect there to be several darkhouses this season, especially on defense. I would say Lewis and Sapp. I also expect one of, maybe even both, J. Smith and C. Miller to finally play up to their potential and have a great year. I think Jancek and Stripling will get the most out of them. Same with Walls. I won't call McNeil a darkhorse because he was expected to be a playmaker when he arrived. I expect him to play a lot in the safety rotation next season.
On offense, Hill and Blanc. Like McNeil, I won't call Crooms a darkhorse because I expected him to be a star before he leaves UT, and with CP and Hunter leaving early I expect Croom to be 'that guy' in 2013.