Saw think link over on Scoble's link blog, and wanted to post about it so I can at least find it later.  Biztalk is something I have been wanting to jump into for a while, but of course never have the time.  When and if that time comes, it looks like this chm might be a terrific starting point.

Check it out here

[UPDATE]
GDN seems to be having issues.  Here is a direct link to the blog of the person who is aggregating this great info.

Check it out here

 [Edit] Added biztalk category.