RE: Mac Pro
Depends entirely on Intel's Xeon product road map. And/or AMD. New Xeon arch "Sunny Cove" is this year. And AMD has Navi coming out July/August - not sure how that will play out with workstation line Radeon Pro cards, since it looks like mid-range consumer? Any timeline will likely slide when it comes to future archs.
But expect a swappable workstation card as an option, otherwise they are just making Darth Trash Can again - something we all hope Apple learned from was a bad idea. Original Mac Pro's used consumer grade cards (both Geforce and Radeon's) with optional upgrade to a Quadro. I don't expect Apple to finally make friends with nVidia again, judging by the current Mojave web driver support, though supposedly Apple is getting feedback from industry pro/sumers for the future Mac Pro. T2(or higher) guaranteed, since well that's the direction they are going everywhere - Xeon's don't have integrated graphics, so I wouldn't be shocked if the future Mac Pro forgo Consumer cards entirely, and relied on T2(+) as the graphics, ever since new Mac mini and MBA has offloaded a lot media handling to their T2's (hardware decoding/encoding). I'm not suggesting it won't have PCIe card support, just that, this would substitute their low powered graphics option that they had to do with original Mac Pro, and pad their margins.
Also just speculating out my butt. I'm a little disappointed the new Mac Pro isn't out yet (think saw rumormill saying early 2019 - well that's come and gone now).
