iOS: Bandito is an app for iOS devices that will sift through your music library to find out what bands and musicians you enjoy, and then uses that information to feed you music news from blogs and music sites around the web.
When launched for the first time, the app scans your iTunes library to learn about the artists that you enjoy. Then it fetches blog posts, reviews and news about your favourite artists from around the web and puts them in one view for easy reading. You can read the articles in the app, or open them in Safari to share them with others.
Bandito is free, but you can only fetch 10 articles at a time. If you want unlimited news and reviews, you can drop $1.99 for an in-app upgrade to the full version. Try the free version first though: depending on how obscure the artists in your library are, your mileage may vary.