I feel the social side of spotify is somewhat lacking at the moment. Firstly, I can't connect with my Twitter friends, who, let's be honest, have much better music taste than my facebook friends, who are mostly people from my high school that I never spoke to. Also there doesn't seem to be a way to find anybody that's not one of your Facebook friends. There should be a way to search for people who have Spotify accounts, regardless of what other networks they're on. It seems like the only way to find people is to search 'spotify:user:usernamehere' which isn't really the most intuitive, and requires trial and error to guess what their username is.
I think the 'People' tab should show a list of people that you're subscribed to, with a stream of activity showing playlists they've made, albums they've listened to etc. and perhaps the ability to post statuses: recommending songs to your 'followers'. Which brings me to another point. There doesn't seem to be any way of knowing who is subscribed to you (as a user, not just a certain playlist). How many 'subscribers' do I have, and who are they? I guess some of these features may be in there already, but if they are, it's not obvious or easy to find.
I think these features would really help make Spotify more engaging, which would be useful now that Rdio is a competitor in the UK, and does social things very well.
end-user should be able to create TAGS for songs. include standard tags like "rock" and "soul", but allow the user to create their own tags, and use this as cross-referenced information to organize not only the user's own music collection, but also to match characteristics of other users' music or playlists. user-created tags would allow Spotify to recommend more musically accurate songs, as the characteristics and style of the songs have been peer-reviewed. it's no secret that Spotify radio is weak. Utilize the social network of Spotify by tapping into the users' knowledge and experience of music.
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