I have posted a document on the HL7 Wiki discussing bindings to terminology and a middle ground proposal for constructing the FHIR RDF coding instance.
http://wiki.hl7.org/index.php?title=File:Terminology_binding_in_FHIR.pdf There is also a link to the document from the FHIR RDF Mapping page http://wiki.hl7.org/index.php?title=FHIR_RDF_Mapping which in turn is linked from the home page for the subworkgroup http://wiki.hl7.org/index.php?title=RDF_for_Semantic_Interoperability I believe that there may be some time next week to discuss it. Always open to comments and suggestions. Tony Mallia