Ohio State led the way, pegged at 11 wins, with Baylor, Marshall, TCU, and Wisconsin following at 10.
Roughly, Vegas sets the over/under to encourage equal betting on both sides. Thus, UVA's number means that the sportsbooks expect there to be about a 50% chance the Hoos win 4 games or fewer, and a 50% chance the team wins 5 or more. (Technically, Vegas is somewhat more bullish on the under, set at -125, as opposed to -115 on the over. In other words, a $125 "under" bet would return $100 - you'd need to bet $115 on the over to make $100.)
The Hoos' over/under takes into account a brutal schedule, which features out-of-conference matchups against UCLA, Notre Dame, and at Boise State, all of whom had over-unders set at 9.5 wins.
Virginia's predicted 4.5 wins ties Syracuse for the second-lowest in the conference, with Wake Forest last at 3.5 wins. Florida State leads the way at 9.5, followed by Clemson at 8.5. Here's a look at numbers for the rest of the ACC, with those of the rest of the NCAA available here: