Many of us have a playlist like "Rock" or "Acoustic/Chilled", and we're all looking for a way to make it the best possible playlist for ourselves by discovering music.
If I have an acoustic playlist with 80 songs, and some random person (Bob) has an acoustic playlist with 49 songs, but 36 of these are in both of our playlists, then I'd love to know what Bob has in his playlist and he'd likewise like to know what's in mine.
I suggest a feature in settings "show suggestions for your playlists" which show up at the bottom of your playlist as greyed out - purely to make you aware of the songs, deleting them shouldn't be a problem, and if you like one or two, then add it to the playlist and more greyed out songs will then appear.
I know it will require a large amount of querying, and a heavy amount of hardware, but the results would be a fluid music discovery service which complements the information from spotify radio.
Sharing playlists is one thing, but music discovery is the most exciting thing about spotify in my opinion. iTunes has Genius - so get ahead of the game.
This idea has been submitted more than one year ago but unfortunately hasn’t gained enough kudos during that time (25 kudos/year). In order to keep an overview of the active ideas in this forum, this idea will be closed for now. Note that this does not mean the idea has been declined by Spotify.
Please feel free to re-post this idea if you still feel you want this implemented. With a little change in presentation, maybe this time it will gain the necessary support from the community.