http://www.apple.com/itunes/playlists/
Be an iTunes Celebrity
Did they like the mix at your last party? Let your friends find the tracks on the iTunes Music Store easily. Publish your playlist as an iMix on the Music Store. Just as with a Celebrity Playlist, you can write liner notes about the picks, explaining your influences. iTunes saves your iMix for a whole year, so you can send your lists to new friends, too. For an iMix, iTunes creates a mosaic of cover art from your purchased albums, just like printing a cover for a mix CD. You’ll see your mix on the album page for songs in your mix, and other iTunes Music Store customers can rate your iMix.