Uhm what about legal MP3 sources (like iTunes) or internet radio (like Last.FM)?

Thanks for your comments guys. You’re both correct of course – there have been many alternative ways to obtain music over the years, both legal and not so legal.

The intention of this post was to show that Spotify could finally bring wayward filesharers back into a more legal environment. This is why I added the keyword POSSIBLE music sources to the title: I don’t think the list would have had the same impact if it included legal Napster, itunes, pandora, etc.