I have heard good things directed towards Newkirk. Bielfeldt after the season mentioned that Josh is a good leader. Newkirk was given credit to a late improvement in defensive play once he could begin practice. While Zeisloft wasn't a stellar defender, Crean gave Newkirk credit for Z's improvement after RoJo went down.
From what I have seen in clips and comments, Josh has a burst of quickness that allows him to put pressure on defenders. He can be a very good replacement if he can get into the lane and make plays without turning the ball over. He won't have to score like Yogi, but he needs to do the other things Yogi did.