I am one of those people who would not have liked the feeling of D2 to be changed with D2R, but honestly, this new game looks absolutely amazing. All of the haters I see must be mad. If there were an easy way to move all the hard work of the devs to D2R, it would probably have to become the new MedianXL. Unfortunately there just isn't.
With that in mind, isn't MedianXL employing a lot of unused resources from D2? These would not be there in D2R, I can imagine, right? So from the start you'd have to recreate models, sprites and a lot of other stuff from scratch, even for the 2012 version.