Yesterday Somasegar (who runs the Developer Division at Microsoft) announced the beta version of the MSDN Wiki - allowing customers to contribute to Microsoft’s developer documentation. 

"In the MSDN Wiki beta, you can add code samples and content directly alongside the Visual Studio 2005 and the .NET Framework 2.0 documentation in a Community Content section that we have added to each documentation topic.  Right now the MSDN Wiki site only features English documentation, but we are planning to expand this functionality to the localized documentation in the future."