With the announcement of Google Music in Europe, I spotted this feature
Now I'm a bit skeptical about this will work. What's stopping someone creating a spoof mp3 file with the same title and a bit of meta data and gaining the real copy when uploading it?
I am sure it'll be a bit more hi-tech than that. Have you ever used the Shazam app? You hold your phone up against some speakers playing an unknown track and it will sample the audio and tell you the name of the track in seconds. Google will use a similar type of tech I would guess.