1. A method of assisting a user in browsing in an electronic catalog of media items, the method comprising: (a) obtaining access to metric values ( 504 ) derived from a knowledge base of mediasets associated with the electronic catalog; (b) receiving from the user an initial selection ( 506 ) of at least one media item from the catalog to define an initial input media set; (c) for each item of the initial input media set, generating at least one navigation list ( 508 ) based on the metric values; (d) communicating the generated navigation list ( 512 ) to the user; (e) receiving from the user an instruction to edit the navigation list ( 514 ); (f) editing the navigation list ( 516 ) as instructed by the user to define a new input set; (g) for each item of the new input media set, generating a new navigation list ( 518 ) based on the selected metric; and (h) communicating the new navigation list ( 520 ) to the user.