Interesting indeed.
It is my view that that majority "SALES" of Windows 2003 Server will on new servers that are just shipping rather than from customers chooding to upgrade their current Server OSes.
I know I don't need it now.
I have customers who are still running NT 4.0 on their PDC's. They have Windows 2000 running on some member servers since these were purchased in the last year or so. They just can't be bothered to upgrade the PDC.