As a way to show what can be done with our data (http://seevl.net && http://developers.seevl.net), we've build a Chrome extension for YouTube that displays contextual information (biography, fact-sheet, etc.) and recommendation for music videos on YouTube. Why ? Because we spend lots of time listening to music on YouTube and thought that would be cool to learn about artists/bands while we're listening to them.
The extension is available from the Chrome Store
https://chrome.google.com/webstore/developer/detail/ifkepnnmiibjoocopfhnglmcoidfeaho
We'd love to get your feedback about it - Thanks !
NB: Backstory: http://blog.seevl.net/2011/06/21/contextube-bringing-context-to-music-videos-on-youtube/