This whitepaper is now available on Microsoft.com at http://download.microsoft.com/download/1/4/d/14d17804-1659-435d-bc11-657a6da308c0/VSvsVPC.doc. Thanks to those of you who gave me comments on the draft.
Abstract: Microsoft® Virtual PC 2004 is a virtual machine solution for desktop operating systems. Microsoft Virtual Server 2005, on the other hand, is a solution for server operating systems. Although Virtual PC and Virtual Server share many features in common, they are designed for different purposes. As a result, some of their features are also quite different. This white paper explains the differences between Virtual PC and Virtual Server and discusses the scenarios in which it is appropriate to use one or the other.