So at WWDC today not only did Apple upgrade it’s laptops and iMacs to Intel Kaby lake processors with more RAM, but they previewed the iMac Pro which will come out in December.
It is a serious pro iMac starting at $4999, with 8, 10 or 18 core XEON processors and AMD Radeon Vega graphics to drive it’s 4K display as well as up to 128GB of RAM. Damn!
Still I would change some things. Intel XEONS are literally generations behind in technology, and their best benefit of using dual processors is useless here. The upcoming i9 processors are much newer tech and also have 18 cores and should be cheaper than Xeons. Even without ICC memory support. And while the Vegas are impressive, I would much rather have an NVIDIA 1080ti for CUDA support.
The fact that Apple is supporting external video cards via Thunderbolt in High Sierra could negate this issue of course, though they only mentioned AMD support.
EDIT: And in a not very pro way, the RAM is not user upgradeable, so you are stuck with what you start ith (very expensive Apple RAM), though at least the 5 grand model starts with 32GB.