Why do we like music?

Why do we like music, or rather, why do we prefer music? In an age when technology allows us easy access to video, we still prefer music. We often prefer text to voice communication, using instant messaging applications instead of making a phone call. The Video iPod was just launched, and I have a strong feeling it won't fly. Sure, people will want to carry the occasional clip around and watch last nights Daily Show while they commute (think Tivo), but it seems to me like video simply doesn't have the same appeal as music. Why?