Not very many in the US....I started listening to it on accident. I found a song on youtube, loved the voices, kept listening, got addicted. :) I love these boys because they're actually famous because they're good, and they aren't just a pretty face with a voice edited to sound good. They aren't hyped up on drugs, they're not spoiled, they're just...people! And their personalities are so great. They have the best sense of humor. I love watching them on the "everyday" sort of videos, they are just adorable and loveable. I think it's the Korean culture, since they're a little more conservative and refined than we are. These boys don't get treated special just because they're famous.