As always, it is difficult to identify whether this rumor is true or what it means even if it is true.
Williams was the nation's leading rushing in 2013, the Doak Walker Award winner as the best running back in college football, and a Heisman Trophy finalist. He's a punishing 230 pound yard back with good speed for a man of his size, the 4.5 range in the 40.
The one thing that leaves me with questions about how he might fit on the Jets is his lack of production as a receiver. Amazingly in a year where he had 2,177 yards on the ground, he managed to not have a single reception. BC had an offense heavily skewed to the run game. A three tight end formation was actually part of their two minute offense. Even so, in an offensive system where the running back is supposed to be part of the passing game, could the Jets have two of three running backs without the ability to make an impact in the passing game?
I do think Williams is going to be a good NFL back, though. My guess is he'll go either late on the second day or the third day. I wouldn't be upset at all to see the Jets scoop him up.