I think that is exactly the kind of niche they are looking to capitalize on. Think about the reasons to buy a powerful workstation computer. Games? You are probably going to build your own custom machine and put Windows on it. Server? Call up Dell and get a rack, or cobble some basement stuff together and throw Linux on it. The other case for needing a powerful workstation today is professional work like video editing, rendering, music production, and Apple already does will in that market. It's clearly one of their lowest priorities, as can be seen by the fact that they updated every other product line multiple times before they came back around to the Mac Pro, but at least they seem to understand the market. If they were marketing this as a gaming machine or a server platform, then they would be making a mistake.