Various versions of FRBR in RDF:

• FRBR core
• FRBR extended on vocab.org (This one was created in 2005 and not updated, so it may be assumed to be abandoned.)
• FRBR entities for RDA
• FRBRoo 
• FRBRer @ metadataregistry.org
• FRBRer (full ontology) (includes OWL)

Models

• IFLA FRBR Review Group
• Murray/Tillett paper model: Cataloging Theory in Search of Graph Theory and Other Ivory Towers
• Rob Stiles relationship model
• Ross Singer's commonThing properties
• SOBR, by Jakob Voss

Implementations

• Librarything
• Variations (Music testbed)
• FaBIO
• Scholarly Works Application Profile (SWAP)

Discussions

• Alistair Miles' analysis and suggestions on DC wiki
• Discussion on W3C LLD list "Disjointedness of FRBR Classes"
• October, 2011
• November, 2011
• Discussion on W3C LLD list "Non- and Partial FRBR Metadata"
• September 2010, starting post

Articles, Blog posts

• The FRBR blog
• Three of the Four FRBR Group 1 Entity Types are Roles, not Types.(PDF) by Renear, AH
• Aggregate Model, (PDF) by Heilbrun Wiesenmueller

Issues:

• Strictness of entities (classes?) and properties condemns FRBRer to a specialist community
• disjointness of classes
• disjointness of properties

     Note: discussion Dec. 2011 with Gordon, TomB and Kcoyle concluded that the strictness is the IFLA SG's intention. Not clear if "someone" should create an un-constrained model nor what that would look like.

• Incompatibility with mainstream bibliographic data (citations, bookstores, book clubs)
• Ross's linking terms commonEndeavor commonExpression commonWork commonItem
• SOBR, by Jakob Voss
• Conceptual nature of FRs vs. encoding as data models 
• Lack of linking to non-FRBR vocabularies  (DC, etc.)
• Acknowledge uses: LibraryThing, WorldCat, Open Library, VTLS
• Reconciliation of versions (above)