Interest in the development of content-based music information retrieval (MIR) systems is growing rapidly. The MIR research community consists of a multidisciplinary amalgam of librarians, digital librarians, information scientists, computer scientists, musicologists, audio engineers, lawyers and business persons. This multidisciplinary approach has given rise to significant technological advancements in retrieval algorithms, audio interfaces and data representation schemes. Notwithstanding these technological advancements, MIR research is currently a systems-centered research domain. For a variety of reasons-including intellectual property law, limited access to substantial, multigenre, multi-format collections and a lack of a historical user-base-MIR research has hitherto been unable to develop and exploit data concerning the nature of real-world user needs and use of music information.