UPDATE: This is an excellent article giving an overview of a lot of contemporary (and not so contemporary) music. The excerpt from the writer, himself a composer, is particularly interesting. Here is, to my mind, the money quote:
The archetypal avant-garde sensibility was captured in the dictum "Make it good or make it bad, but make it new." I suggest that it's time to take that attitude out behind the barn and shoot it. Standing in the middle of the sometimes interesting chaos and anarchy that is the scene in all the arts, I suggest in its place: Make it old or make it new, but for chrissake make it good. Over the years one has encountered too many splendidly innovative, yet boring and annoying works of art.Oh, heavens yes! I think this is exactly what I was saying in a few different posts. There is such a thing as good music and bad music. A composer should really be trying to write good music--doncha think? One final thought: isn't it odd that so much of the musical style of the avant-garde has found its true métier in the soundtrack to horror movies? It's a perfect fit!
UPDATE: A lot of people seem to be finding their way to this post via the Slate article. Welcome! Here is another post that you might find interesting: http://themusicsalon.blogspot.com/2011/07/beauty-and-music.html