They then proceeded to add nothing in 10.9, 10.10 or 10.11 to actually use both at the same time, since one is dedicated to display another the other to compute tasks. Leading many to question what the ****ing point was. And even then, why not use existing standards? MXM for graphics. M.2 for PCIe SSDs. The value proposition for this machine is hard enough to justify as it is, and alright, perhaps the majority sold won't have the hardware upgraded in any way over it's expected 4 year lifespan, but what about after that?
If my 2010 Mac Pro has a hard drive, CPU, RAM, GPU or fan issue, I can definitely do something about it. If the logic board or PSU go then that's a concern, but there you go.
But in this new design, once Apple declare it obsolete, what do you do? Buy a new one I guess is the familiar refrain. No thanks.