PlayListID | Track1 | Track2 | Track3 | Track4

SELECT Count(*) AS score, songs.name
   FROM playlists AS myPlayLists
   JOIN playlists AS otherPlayLists
      ON (otherPlayLists.songPK = myPlayLists.songPK)
   JOIN songs
      ON (songs.songPK = otherPlayLists.songPK)
   WHERE  myPlayLists.ownerPK = ?
   GROUP BY songs.songPK
   ORDER BY Count(*) DESC, songs.name

USE test
GO

IF EXISTS (SELECT NULL FROM sys.tables WHERE object_id = OBJECT_ID('dbo.play_list')) 
BEGIN
    DROP TABLE dbo.play_list
END

CREATE TABLE dbo.play_list
    (
        playlist_name       VARCHAR(50)     COLLATE Latin1_General_CI_AS    NOT NULL
      , track_ordinal       TINYINT                                         NOT NULL 
      , track               VARCHAR(90)     COLLATE Latin1_General_CI_AS    NOT NULL
      , CONSTRAINT pk_play_list PRIMARY KEY CLUSTERED (playlist_name, track_ordinal) WITH (FILLFACTOR = 100)
      , CONSTRAINT ix_play_list_track_ordinal_track_u_nc UNIQUE NONCLUSTERED (playlist_name, track) WITH (FILLFACTOR = 100)
    ) ON [PRIMARY]
GO

INSERT INTO dbo.play_list
    (
        playlist_name
      , track_ordinal
      , track
    )
VALUES  ('Playlist 1', 1, 'Fly')
      , ('Playlist 1', 2, 'X')
      , ('Playlist 1', 3, 'Y')
      , ('Playlist 1', 4, 'Z')
      , ('Playlist 2', 1, 'X')
      , ('Playlist 2', 2, 'B')
      , ('Playlist 2', 3, 'Q')
      , ('Playlist 2', 4, 'L')
      , ('Playlist 3', 1, 'Fly')
      , ('Playlist 3', 2, 'Z')
      , ('Playlist 3', 3, 'Y')
      , ('Playlist 3', 4, 'Q')
      , ('Playlist 4', 1, 'Fly')
      , ('Playlist 4', 2, 'Z')
      , ('Playlist 4', 3, 'Q')
      , ('Playlist 4', 4, 'L')

SELECT  TOP 5
        recomended_track                = recomendations.track
      , recomendataion_weight           = COUNT(*)
FROM    dbo.play_list                   AS base
INNER JOIN 
        dbo.play_list                   AS recomendations
ON  recomendations.playlist_name        = base.playlist_name
WHERE   base.track                      = 'Fly'
    AND recomendations.track           != 'Fly'
    AND recomendations.playlist_name   != 'Playlist 3'/*Assuming the person doing the search compiled this playlist:
                                                        we would not want to return any tracks from it in the results.*/
GROUP BY
        recomendations.track
ORDER BY
        COUNT(*) DESC