McClung to the Rotation, Villy to the Pen

Word from JSOnline that the Brewers have shifted around their rotation significantly, switching Bush and Suppan and moving McClung into Villy's spot.  In theory the latter is temporary, but obviously we'll see.  I'm not sure what this does to make the rotation any better, but maybe it somehow makes the bullpen better.  I don't know why they made the other move.  Something about matchups?  Or the style of the rotation?