How do teenagers learn about new music? Audrey LaPlante has spent some time actually asking them, and presented some of their answers at the Workshop on Music Recommendation and Discovery.
Some of her findings were extremely interesting. All of the teenagers she spoke to said that their tastes had changed substantially over time, and that the changes were due to changes in their social network. Most had music geek friends whom they actively consulted for music recommendations, even though they were not influential people in other respects. Although close contacts were most likely to be sources of new music, those chosen to play that role were "almost always those whose social network were more different from theirs, mostly those who were going to a different school".
I'll be interested to follow Audrey's research and see how we can learn to make online social networks an equally great place for young people to discover new music.