ESPN radio has been reporting for a few days now that Rashard Mendenhall seems poised and ready to usurp Willie Parker as the starting running back for the upcoming season.  Personally I think the assessment is a bit premature.  Assuming that the Steelers will use the two-back system in 2008; who do you think is going to get the nod to be listed first on the depth chart this season, Willie Parker (who's coming off of a broken leg in 2007), or Rashard Mendenhall, the much anticipated rookie?