We (Quest Software) recently published a web page with a list and description of our "experts". Very useful information for me because even in a 3,000 person organization you don't get to meet everyone plus we are a global organization and expertise exists in more places than the United States after all.
In the Microsoft area there are nine chaps featured on the page. Check them out. Their expertise crosses Active Directory, Exchange, PowerShell, SharePoint and Identity Management. In fact, a couple of them are MVPs (Microsoft Value Professionals).