Not particularly. My users don't understand it. Google Apps has been fighting this for some time in both Gmail and Google Docs. Users are used to folders, but Google uses tags and collections. They used to call collections (Google Docs) folders, but the fact that a document could exist in two 'folders' confused the hell out of my users.

As it turns out, the benefits of a tagging based approach don't pay out nearly as much as the user training and maintenance costs.