The only slight difference is the fact that the Apple logo is now not simply printed on the back cover, but is actually now an inherent part of the actual rear housing.
The fact that Apple has allegedly decided to keep the aluminum body unchanged basically means that it’d need to really deliver on what’s under the hood and that’s where the most innovation should come in the iPad mini.
Apple is obviously seeking to unify the looks of its iPad family. Yesterday we saw important changes in the rear aluminum back of the 9.7-inch iPad 5 - it becomes narrower and has an iPad mini like design.
Keep in mind that the images below look realistic, but there is no proof that would confirm they are indeed real, so take them with a grain of salt. You can still though examine the aluminum rear housing of the upcoming second-gen iPad mini right below, do you see any changes?