Technically I guess a "real pro" can work on any machine, even a 2008 MacBook. We here are all more arguing what was expected for a top of the line flagship MacPro machine. We got a miniPro, when there could have been so much more. If there ever was a machine to throw everything possible into it, the whole kitchen sink, it's the pro. It sells low numbers already, so why not build it into a monster beast that other computers fear?
Again, I think the machine Apple has shown does have a place in the lineup, I just don't think it should be replacing the current MacPro.