Spotify finally launched in the United States today, much to the joy of music-lovers. But for Sean Parker — a Spotify investor better known for co-founding Napster and his early involvement in Facebook — said that the service is the one that finally realizes the social potential of online music.

In a note on Facebook, Parker said that is “the answer to piracy,” as it lets users share their digital music organically.

Spotify is “migrating millions of piracy-based music fans to a legitimate platform where their consumption of music can be monetized and the artists who dedicate their lives to creating music can finally get paid,” Parker wrote.

By making it easy to find and share music, Parker predicted that Spotify’s U.S. launch will lead to renewed growth in the music industry.

According to the company’s release announcing the launch Thursday morning, founders Daniel Ek and Martin Lorentzon started the service “out of a desire to develop a better, more convenient and legal alternative to music piracy.”

Of course, Spotify has a lot of competitors who are already successful in the United States — Mog, Rdio, Grooveshark and Pandora, to name a few — so it seems unlikely that it will single-handedly end the piracy problem.

Still, Parker’s comments do point out that piracy risks are fast outweighing their benefits.

Does pirating still appeal to you as a way to get music? Or do online services get you enough of the music you want while staying within the law?

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