Technical Bulletin 255, “OCLC-MARC Format Update 2008,” describes the changes to OCLC-MARC records based on update 7.
Some new subfields, e.g. relator codes for X11 fields, and a couple of new indexes have been created. 047 Form of Musical Composition Code has been updated a bit allowing for IAML musical composition codes to be used and indexed. They’ll all be ready for use in June 2008.