I agree with sigpig that JoJo Walker has shown good potential as a receiver but, other than one nice punt return that was called back due to a penalty, he has not yet been able to break past the first wave of tacklers on punt returns for whatever reasons.
Ironically, when JoJo Walker was at Maryland (2002-2005), the first string kick/punt returner from 2002 to 2004 was Steve Suter (2001-2004), who played briefly for the Ticats in 2005. Unfortunately, Suter sustained a serious injury to his shoulder twice within the first six weeks of the 2005 season and either retired or was released by the team.
As a point of interest, here are the career college stats of JoJo Walker and Steve Suter at Maryland:
Kick Returns- 49/1081, 22.06 avg., 0 TDs
Punt Returns- 35/261, 7.46 avg., 0 TDs
Kick Returns- 52/1259, 24.21 avg., 0 TDs
Punt Returns- 121/1271, 10.50 avg., 6 TDs