I've used Last.fm for a couple of years now, logging (or, in their terminology, "scrobbling") over 58,000 tracks as I listen to them. It's kind of your music player's "most played" list on steroids, as it's cross-compatible with everything.
Last.fm also works with local event listings, as well; they've just released a new app called "Festivals" that will hopefully find its way to music fans' phones everywhere.
Festivals works like a trip planner to make sure you get the most out of your festival experience. It provides you with a list of shows that are occurring during the day, as well as matching your compatible tastes according to your Last.fm account.