If you have a .net application running on 2.0, test it on the 2.0 shipped in Vista, even if it has no UI. .Net 2.0 on Vista is not the same as the 2.0 that's available on other platforms right now.
The Synopsis
On Vista (RTM), System.Xml.Dll's file version is 2.0.50727.312.
On XP with either .net 2.0 or .net 3.0 installed, it's 2.0.50727.42
The serialization engine that creates xml serialization assemblies on the fly (via XmlSerializerFactory or XmlSerializer) creates markedly different assemblies
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