I don't see it that way at all. The Mac Pro has always been about the top 1% power users. The appeal was twofold: it was a bitchin'-fast machine you could stuff with as many cards and drives as you want, and it ran OS X.
This new design removes the former selling point. 12 core max (same as current)?? Four RAM slots (down from eight)?? 1/6th the volume (i.e. space to plug stuff in)??
This offers almost no advantage over a late model iMac with a Thunderbolt-to-PCIe breakout module (which is what many power users have been doing in the years since the last update).