Found this in one of the comments:
2012/01/12 at 6:54 pm
Can you tell us Nnamdi’s stats this year?
2012/01/14 at 12:02 pm
571 coverage snaps, targeted 47 times, allowed 29 catches (61.7%), 376 yards, QB rating against of 88.6.
Rick Drummond is an editor for PFF so I don't think he would lie about those numbers he posted.