Visio 2010 Add-in for Exchange Server 2007 is a great tool that lets you quickly build a diagram of your messaging infrastructure.
This Microsoft Visio Add-In makes it easy for Exchange administrators to visualize, explore, and communicate complex information. Instead of viewing single user data, administrators can create data-connected Visio diagrams that display data at a glance and dramatically increase productivity. You can diagram a Microsoft® Exchange Server 2007 site topology, including sites, servers, and connections
Although Exchange Management tools are invaluable for managing, monitoring and administer networks, computers, services, and other system components it does not provide a graphical view of user mailbox details. Administrators have to sift through a tree view to view the members of the Distribution Group in an organizational unit and use embedded data to figure out the details.Microsoft Management Console (MMC) hosts administrative tools that you can use to administer networks, computers, services, and other system components. Exchange Management Console and Exchange Management Shell are used to administer and configure specific settings for Mailbox servers and create and manage Mailbox objects.