Keeping track of music is never an easy feat when you have a lot of it. Beathound is a new web app that takes your uploaded iTunes XML file and fills in the blanks in your collection, recommends new stuff to check out, and emails you with new releases from artists in your collection.
To start, you need to upload your iTunes XML file ("Users/[your username]\My Music" on Windows, "[your username]/Music/iTunes" on Mac) to Beathound. After a few minutes of analysing the file (time depends on how big your iTunes library is), Beathound will show you a list of the artist's albums you're missing in your collection. Once it has done with that, Beathound emails you to let you know when recommendations are ready (it takes a little while) and will send you an email each week with new releases suggested directly for you (you can opt out directly in your first email if you prefer).