Browsing MSDN this morning and saw the note that they now have Wiki support. If done well it could be tremendously powerful to get not just the official MS line but also the hard lessons learned that you often run across in forums and community generated articles. I haven't looked yet to see if they support adding new topics, it would definitely be limiting if we can only extend existing topics.

http://msdn2.microsoft.com/en-us/library/ms130214.aspx