eWeek [0] let the cat out of the bag a bit early it seems.
Virtual Server 2005 is Virtual PC 2004's big brother designed to run server operating systems and applications.
Pricing doesn't seem too bad. $499 for the standard edition. However, the machine you run it on in production does require a valid Windows 2003 Server license.
Note, you can run Virtual Server 2005 on Windows XP Pro if you're doing development work.
I'll post some more entires over the next couple days about why one vs. the other.
[0] http://www.eweek.com/article2/0,1759,1644226,00.asp
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