Atonality, on the other hand, is a more recent development in Western music and is defined as the lack of a tonal center. Atonality can be an extremely interesting way to write music. Some of the first atonal music (note how it's not markedly "dissonant") can be found in Debussy's Prélude à l'après-midi d'un faune[1] and the prelude to act I of Wagner's Tristan und Isolde [2].
I don't listen to a huge amount of pop music, but is there anyone out there that is at least experimenting with atonality?
[1]http://www.youtube.com/watch?v=9_7loz-HWUM [2]http://www.youtube.com/watch?v=1Bwl3GYBM3E