Microsoft SharePoint Site now on SharePoint
Ian Palangio wrote about how Microsoft is using SharePoint for it's content management in their SharePoint site. He also shares more sites using MOSS 2007.
http://blogs.msdn.com/ianpal/archive/2009/05/21/microsoft-sharepoint-site-now-on-sharepoint.aspx
Here is the great resource on MOSS 2007 best practices. Best Practices Resource Center for SharePoint Server 2007