1. A computer implemented method comprising: obtaining access to metric values derived from a knowledge base of predefined mediasets, each of the predefined mediasets comprising a plurality of media items grouped together by one of a plurality of users into a playlist, wherein the metric values reflect a relative frequency within the predefined mediasets in which a first media item and second media item occur together; receiving an initial selection of at least one media item to define an initial input set of media items, wherein the at least one media item occurs within at least one mediaset in the knowledge base of predefined mediasets; generating an output media item navigation list responsive to at least one media item in the input set of media items, wherein the generating is based on the metric values derived from the knowledge base, and further wherein each media item in the output media item navigation list occurs in at least one mediaset in the knowledge base of predefined mediasets; receiving an instruction to edit the initial input set of media items responsive to the output media item navigation list; editing the initial input set of media items based on the received instruction to define an edited input set of media items; generating a new output media item navigation list responsive to at least one media item in the edited input set of media items, wherein the generating is based on the metric values; and creating an interactive browsing session by iteratively repeating the steps of receiving an instruction to edit the initial input set, editing the initial input set, and generating a new output media iten navigation list.