The test results have been updated to include the 2.7 GHz 2013 Mac Pro in about half the tests; the remainder will follow shortly.
So far, the 12-core and the D700 GPUs are both duds or only marginally better than the D500 GPUs with most photography applications.
Put another way, you’d better have a darn good reason for going past 6 cores and/or getting the D700 GPUs. The sitution is fluid and might well evolve over time, but for now it’s clear that the 6-core is the ideal machine for most users, and that those looking to eke out modestly more performance should go with an 8-core 3.3 GHz CPU upgrade (from a 4 core).
Bleeding edge—the D700 GPUs show a curiously inferior performance on some tests to the D500 GPUs. Barefeats.com reports a similar confounding result in the FCPX Render Gaussian Blur test and others (D700 GPUs test slower than D500 GPUs). Perhaps it is a drive issue or other issue that will get fixed, because the Unigine Valley demo, shows frame rates about 50% higher with the D700 GPUs.