You've probably already read about the MSDN Wiki Beta on Soma's blog. You can now add information to MSDN content for Visual and the .NET SDK. I think this is great, and I hope it expands to the rest of MSDN. Some of the things that I particularly like:
- RSS feeds for everything.
- you can edit existing blocks.
- it tracks who made what changes. For example, I can see all of the changes by Adam Nathan here.
- it separates the community content from the official MSDN content. I come to appreciate this after reading Wikipedia and always wondering if what I'm reading is true. Easily knowing where the information comes from lets you judge the veracity. (This is equally important in the case where MSDN is wrong and a credible community member offers a correction).

I've made a few posts (my history log is here). The subsection on ICorDebug is Maybe I should go add the information from my "This should be in MSDN" posts.

Check it out and add your own information!