I agree. Looking at the top 10 torrents (best seeded) on the "most popular" private music torrent sites (each with over 100,000 users) a small segment is on major labels. Those that are on a major label are quite old and not heavily marketed to the youth anymore. Like Miles Davis- Bitches Brew. Meanwhile acts like the Black Lips, Blue States and bed room dj DJ frane are dominating the top 10 lists. These trackers place no restriction or bias on the type of music or copyright of the music torrented.
While this does not represent the general cross section of people using torrents, it does represent what happens with bittorrent "communities". People discuss, share and promote artists that are fresh and interesting.
Unfortunately gaining access to these private communities requires a slight bit of savvy not present in the general population yet, so I am sure that biases the poll. However if it were not for the legal status of these sites in many countries the barrier to entry would be 0.