beaTunes is an iTunes companion app capable of automatically analyzing your music collection to help you build better playlists. It analyzes BPM (beats per minute), silence at the beginning or end of a song, and the color (based on frequency spectrum) of a given song. Some of the data is stored through iTunes, and some is stored by beaTunes itself. beaTunes can suggest albums that would complement your music collection, display music charts, and help you find and fix errors in your song meta data, like typos and wrong genres. It also allows you to blog about selected songs or playlists.
A workaround was added for a long-standing drag and drop bug for files with non-ASCII characters in their name on Mac OS X.
URL: beaTunes ~ build better playlists