I think this is RIP to the Mac Pro for anyone that cares about extensibility. I can't see Apple making a board with a socketed CPU of their own silicon. I'd even say something like RAM would be a stretch.
Yea, I wonder what the Mac Pro is going to look like in a couple of years. Then again, they could stuff it with 100 A19z processors and have a 1024 thread machine (or something equally outrageous).
I have to think it's going to be tiny, cool (as in temperature) and use a fraction of the electricity that the latest Mac Pro does.
As for the pro software that currently requires a physical dongle for DRM, I'm guessing those vendors will be forced into the Mac App Store with Apple managing access to the software for them.