iLike is a kind of social networking community built around iTunes. It comes in the shape of a sidebar that will display recommended artists based on the music you usually listen to.
If that weren't enought, iLike allows you to download music for free, from the available tracks on GarageBand.com. Being a social community, you'll also be able to create your own personal user profile and share your music tastes with other people.
iLike's interface lets you discover new artists and download music, but also see what your friends are listening to, leave comments on their profiles and, of course, buy tracks online through iTMS or Amazon.