Spent some time to understand SharePoint 2010 meta-data service and the steps to activate it. The meta data service works as the rest of the SharePoint services by creating a service proxy in your farm. Besides, in order to make this available for your site collection, you need to grant site app pool service account permission to the newly created meta-data service. Otherwise, you would get an error message telling you that the service proxy is unavailable.
Then, you can start adding users to be term store administrators for managing and approving document keywords for tagging. They can be built in hierarchical structure to mimic your organizational chart. This tree structure can be used as site menu for navigation. Moreover, these keywords become available instantly in search box. Nice!
SharePoint 2007 does not have this feature. In my opinion, it is hard to claim your site as a content or document management system without a customizable meta-data search-engine. ;)
