Brian Calhoun fell further than he'd planned, to #74 in the third round with the Detroit Lions.
What you have to consider, though, is that we was only the 7th back taken. The first five were household names of Reggie Bush, Deangelo Williams, LeDale White, Joseph Addai and Lawrence Maroney. So yeah, he fell to the 3rd round, but beyond Bush, it really wasn't a first day for backs.
Wisconsin WR Brandon Williams was also selected in the 3rd round, at #84 by the 49s. Williams was the 7th overall WR selected.