Ok, so a bit late, but the Beta 2 release of Visual Studio 2010 was released two weeks ago. With Beta 2 come a number of changes to the DataContractResolver, so I’ve finally found the time to update my previous post. For those that have read the post during Beta 1, ResolveType has become TryResolveType and returns a bool indicating whether the resolution was handled or not, both resolution methods now take a declared type parameter, and you can return true from TryResolveType and set typeName and typeNamespace to null to indicate that you do not want any xsi:type written out on the wire, enabling you to serialize a type as the declared type.
Also new with Beta 2, I’m in love with the new Lightweight Beta view for MSDN documentation. Try this out: http://msdn.microsoft.com/en-us/library/system(lightweight).aspx. It loads much faster, it’s cleaner, and it still lets you filter out the language you want (unlike the ScriptFree view).
I’ll be adding more posts about the other new WCF-related features in Beta 2, so stay tuned.