I try wordpress 3.5.1 and 3.5.2 preview image doest show up.
Main page: http://img46.imageshack.us/img46/2185/loo6.png
Post: http://img855.imageshack.us/img855/8571/obdf.png
Main page: http://img46.imageshack.us/img46/2185/loo6.png
Post: http://img855.imageshack.us/img855/8571/obdf.png