The MAPI docs have been revamped and moved from Exchange to Outlook 2007 in MSDN. As Thom points out - they did great work on these updated docs. Steve also has a post about this along with an overview. If you are interested in MAPI, go check them out!
PingBack from http://blog.a-foton.ru/index.php/2008/12/05/fyi-the-mapi-docs-have-moved/
I read couple of related blogpost's related to MAPI documentation. You can start reading from Sgriffin
MAPI documentation has been moved from Exchange tree to Outlook tree with Outlook 2007. The documentation