I just realized that RDF has a lot in common with MARC, the standard catalogging format for library data. Both categorize similar types of data and maintain similar pieces of information. MARC was developed long before the web, but there’s now an XML standard for MARC records.
Specialized software is used to catalog, maintain, and browse MARC databases. It would be interesting of RDF and/or XML can replace MARC. BTW, I used to work for that company and helped develop a client application for the Mac, which was discontinued after I left, since they couldn’t find another Mac programmer 🙂