You may be right that, in some respects, "cultural objects are substantively different than news articles", but not in ways that are germane to this argument:
"The news is largely valued for its accuracy, timeliness, and topical relevance to a reader. Music and other cultural objects are valued for their enjoyment, which is contingent on individual personal preferences."
I addressed this in an earlier response..."personal enjoyment" of music is inexorable from "timeliness" and "relevance."
I get more "personal enjoyment" from John Zorn than anyone else, but I don't wanna hear it when I'm making out with my girl, or at a club.
Think about the success of mood/circumstance specific mix CD's like "Ibiza Club" or "Ellington for Lovers"...
Musical preferences have a lot more to them than "people like you also like"...
Also, with all the choice available, it's easy to overestimate people's desire to even HAVE choice.
Finally, I am imagining a more sophisticated metadata model that is not just about creating categories for things. I don't really have the details on that, though ;-)