Scott just announced it:http://weblogs.asp.net/scottgu/archive/2007/10/03/releasing-the-source-code-for-the-net-framework-libraries.aspx
This will make debugging .NET apps a lot easier...
More details on how this is going to work exactly on Shawn's blog:http://blogs.msdn.com/sburke/archive/2007/10/04/channel-9-video-more-details-on-reference-source.aspx
UPDATE: this is now available. See the following posts for details:http://weblogs.asp.net/scottgu/archive/2008/01/16/net-framework-library-source-code-now-available.aspxhttp://blogs.msdn.com/sburke/archive/2008/01/16/configuring-visual-studio-to-debug-net-framework-source-code.aspx
wow, that is big news!
This is great news. I remember the source code was shipped with the good old MFC. There was even a book "MFC Internals" which was a guide line to the MFC source code. Very good if something doesn't work as expected.