Doesn't DO much, but allows the specification of relationships between nodes. The problem is that Dublin Core (the metadata specification which RDF uses) overlaps with many existing data structures in Drupal core. Examples:
- Authored by
- Is a version of
The natural inclination is to adopt Dublin/RDF into core, exposing relationships implemented by the system as (read only) RDF attributes and respecting relationships defined by the user. This would greatly simplify Drupal core, but would require considerable restructuring.
This demo site also has the admin pages for RDF opened up for Anonymous: http://coders.co.nz/drupal_development/?q=admin/relationship