This article will focus on music indexing and retrieval from different points of view. Four elements will be examined: music metadata, indexing and retrieval methods (classic indexing, collaborative indexing and social tagging), tools and users. Regarding the users, we will look at their access modes, their possible participation in indexing, and their music information-seeking behaviors. Do they look for music information in pay-for-music sites (iTunes), radio stations, blogs, or social networks (MySpace, YouTube, etc)? The question we raise is which music information systems would be suitable in a social web era. An evaluation of the existing indexing and retrieval modes was conducted. It was based on both quantitative and qualitative approaches. Our research methodology used interviews, online questionnaires and semi-directed questionnaires. We believe that the results of our evaluation will be useful for music information indexing in a Socio-Semantic Web context.