It would be nice to be able to open up the registration system to more people not just Facebook. This idea will never disappear. I figued I'd post it here in this lovely new community of Spotify.
We’re delighted to offer our users yet another way to sign up to Spotify. New users can now get instant access to millions of songs simply by visiting www.spotify.com and providing an email address and username. People can also continue to sign up and log into Spotify with Facebook across iOS, Android and web for easy access to the ultimate social music experience.