I'd distinguish between the professional market and enterprise. Look at the lengths Microsoft goes to in order to maintain backwards compatibility for their en

I'd distinguish between the professional market and enterprise. Look at the lengths Microsoft goes to in order to maintain backwards compatibility for their enterprise customers, Apple in comparison just doesn't care. Obviously I don't have access to the sales figures but my guess is most Mac Pros are going into audio/visual studios or else high net worth individuals. It's not the sort of thing enterprises will buy if they can avoid it.