By tapping into the last.fm API, these Irish researchers modeled the geographic flow of musical influence. They were able to identify where certain tastes frequently originated, and draw a hierarchy of influential cities (like the chart shown above for North America).
Surprisingly, the size of a city doesn’t associate very strongly with how influential it is. That means that despite its enormous size, NYC isn’t that much more influential than Portland or Austin. There are prevailing theories that large cities are the drivers of cultural invention, but this seems to show (for music, at least) that a connected online world is leveling that playing field.
Also, they have a graph displaying “Normalized Radiohead vs. Normalized Coldplay”, which has to go down as one of the best figures in a research paper, ever.