^Discovered a subgenre called "Math metal" - it's what I would
  have called "Progressive metal" (like progressive bands like
  Yes, etc) - anyway - it's bands that use ever changing time
  signatures. The vocals suck to me (roar, roar, roar) unless
  that's what you like -- but the music behind it, the timing, I
  appreciate. It's NOT easy doing odd timing - especially in
  composition - the screaming vocals are the easy part - and it's
  the style - but the musicianship in the timing, the geometry is
  anything but easy. I just mentally blocked out the "roar roar"
  and listened to the instruments. (a couple of the vocalists were
  good though) http://www.youtube.com/watch?v=8bJ5F0YD3_4
  ^