One you switch an MSDN library page into Classic view, you can't switch back.
The buttons in the top right corner do nothing.
As a quick fix, I tried deleting browser history and cookies, etc, but I still can't get back. Annoying! You can switch from Lightweight or Scriptfree to any other view, though. It's just that one page where I switched to Classic that I can't get out.
Thanks.
Love XNA, love WPF and Blend