If these rumors come to be, the 7" iPad will be the one to semi-permanently install in a compact Mac. That way, the dock connector will fit and the the home button will be accessible in the black border around the screen, which will look much more like the way a compact is supposed to look. It will probably require much less modification than than the current dock.

http://www.ilounge.com/index.php/backstage/comments/leaked-details-on-2010-2011-ipods-iphone-5-bumper-2-ipad-mini/