Unless Stepfan Taylor goes down early in the season I don't think Tyler Gaffney will be missed.
They ran mostly by committee last year and Stefan Taylor ran for 1330 yds. He's expected to be a bell cow in '12. They lost Stewart and now Gaffney but return Wilkerson who moved ahead of Gaffney, Seale, redshirt Remound Wright and a rookie named Barry Sanders.
Luck's scrambling will be missed but the FBs are a load and will get more work. Hewitt is 243 and Meinken 256.
Biggest impact might be the OLine. They lost DeCastro (1st Round) and Martin (2nd Round). They have talented backups but lack the career starts of last year's group. The OLine allowed 6 sacks last year (some credit to Luck also) while the Team rushed for 211 yds/game. In the last 3 years the OLINE had the 3 best school rushing season while only allowing 24 Total Sacks. The Sacks should go up but the new QB should get good blitz protection from an experience and beefy backfield.
2011 Rushers:
RB
Taylor 242 carries, 1330 yds, 5.5 ypc, 10 TD
Gaffney 74 carries, 449 yds, 6.1 ypc, 7 TD (GONE to MLB)
Wilkerson 56 carries, 282 yds, 5.0 ypc, 3 TD
Stewart 55 carries, 257 yds, 4.7 ypc, 9 TD (GONE)
Seale 6 carries, 23 yds, 3.8 ypc, 0 TD
FB
Meinken 12 carries, 90 yds, 7.5 ypc, 0 TD
Hewitt 10 carries, 35 yds, 3.5 ypc, 0 TD
QB
Luck 47 carries, 150 yds, 3.2 ypc, 2 TD (GONE)
Nottingham 1 carry, 10 yds, 10 ypc, 1 TD
WR
Owusu 2 carries, 78 yds, 39.0 ypc, 0 TD (GONE)
Montgomery 2 carries, 42 yds, 21.0 ypc, 1 TD
Terrell 1 carry, 4 yds, 4.0 ypc 0 TD
Gatewood 1 carry -2 yds, -2.0 ypc, 0 TD (GONE)