Eg, why are we still using playlists? I want to be able to sort/listen to my music by tags, ranging from "cool" to "energetic" to "happy". Ie, a string tag, a tempo tag, and an emotion tag. I want to be able to filter queries to an arbitrary number of tags and genres. I want to be able to filter by who it was produced by, who played in it, per album or per song.
Most of the features i want don't require any complex content recognition algorithm. And yet, like it's 1990, most of the music apps i use (spotify, google music) lack what i consider to be basic features.
Why did Gmail "pave the way" with tagging instead of folders, and yet i'm still stuck using Playlists in Google Music? Why does Spotify support a nice rich community for playlists, but seemingly won't let the community add meaningful data to songs, albums, etc and then let me query my song collection from that?
I know, i'm sure there are plenty of mp3 players and etc that do this just fine - but i use Spotify, and i want the features in there. I want a streaming collection of on demand music. I like the variety. I'd kill for my above features with a Spotify-like package.