Last night, I installed Windows XP Professional in a virtual PC on Nighthawk using Virtual PC 2007 running under Vista Ultimate x64 (RTM Build 6000.) The installation completed without a problem.
Even though the Windows XP Professional installation ISO image included SP2, there were still 72 "high priority" and 11 "optional" updates to be downloaded and installed! The optional updates required another 5 high priority updates.
I updated Internet Explorer to Version 7 and that required another 2 high priority updates.
I am pleasantly surprised by the performance of the virtual PC running Windows XP Professional. The virtual PC has 1 GB of real physical memory allocated to it, which probably contributes to the good performance. I am sure that Vanderpool Technology (Intel's virtualization technology) also has a lot to do with this good performance.
With this successful test of Virtual PC 2007 and the installation of Windows 98SE, Ubuntu 6.06 LTS, and Windows XP Professional on virtual PCs all running under Vista Ultimate x64 (RTM Build 6000), I am now in the process of installing Windows XP Professional in a virtual PC using Virtual PC 2007 on Blackbird, which is also running Vista Ultimate x64.
This will allow me to retire my Pentium III PC running Windows XP Home Edition. The reason why I have been keeping it around is to run software which does not run very well, if at all, on Vista Ultimate x64. This setup will allow me to run all programs which I use under Windows XP Professional or Vista Ultimate x64 on the same PC without requiring re-booting.
This Pentium III PC which has 2 GB of memory and 880 GB of disk space will be relocated to my "server" closet and re-purposed as another server running Windows Home Server, assuming I am selected to participate in the Beta program.