• music (songs, albums, bands/artists, genres(?))
• movies (also writers, directors, producers?)
• tv shows?
• books, authors
• people (dating)

Enter artists/titles of favorite songs
or favorite albums
or favorite artists

or export/link to your playlists

Website has four mechanisms for finding songs/artists/albums you'll like:
-Finds songs/artists/albums that are frequently liked in the same playlists with a given song/artist/album
-Finds s/a/a's by ranking others' playlists according to how many songs you like they have in them divided by the numbers of songs in the lists, or maybe (also?) according to how many songs they like that you have, and every file contained in every one of those playlists gets its rating increased by the aforementioned rating every time it occurs in one of the lists.
-If you hear a s/a/a and you know of another one that's similar to it, you can submit the reference. That data can then be used to correlate favorite songs with other songs.
-Users can look at other users' lists and suggests songs/albums/artists to them.
-adding now: AI - can figure out a manifold of invented variables that underlie what a person likes vs doesn't like

Users can submit multiple playlists and have the system treat them as separate islands, for example to isolate by genre, thus making it easier for the AI.

Users can choose to ignore, or downplay, suggestions for songs by artists or albums they already have songs from, since they might already know about them all. Or actually, you can click on any artist or album in the results and tell it to filter out that artist or album.

website supports playable playlists like playlist.com? we'll see if playlist.com gets convicted..

The four mechanisms and the multiple lists ideas also apply to the favorite movies lists.

The four mechanisms, the multiple lists, and the artist filters also apply to the favorite books lists.

while the system does not have explicit delineation of movie or song genres, because there really are no solid dividing lines, for books you may want to allow it to discriminate between fiction and non-fiction, and perhaps even romance, fantasy, psychology, physics, medicine, chemistry, molecular biology, cosmology, autobiographies, biographies, mechanics, electronics, self-help, science fiction, various informational technologies, and so on and so forth, because the lines are clearer.