I downloaded the first Clemson vs. VaTech game to get a feel how VaTech plays. One thing that I noticed right away is that VaTech looks like they run a 4-2-5 or a Nickel. I did some searching and came up with this article from Chris Brown on Dr. Saturday's blog.
Essentially, VaTech started out with a 4-4 Cover 2 and slowly evolved to a defense that looks more like a Cover 4. I'd say it's a must read for anyone who wants to scout our next opponent.
EDIT: Actually, now that I read through some of the comments, I realize why this seems so familiar. At first, I thought it was the 4-2-5 like at TCU, but now I realize that it's more like what we had with the spur and bandit in 2009 in terms of alignment and personnel, but a different philosophy.