Bah, Korn and Disturbed and all the other shit are just anger menagement tools, people only like it because it's full of yelling and complains about a hard relationship or other social situations that provoke an angry emotion.
That's not metal
It might mix up gayer sides of punk and death growls and other stylistic things in an effort to mix up the "best of both worlds", underneath all the appeareance it will just be mediocre rock music that looks unappealing to anyone who isn't braindead.
That is not metal
Dragonforce and Opeth and Meshugah just make "technical" music to imitate Helstar, Atheist or Gorguts. It's just badly done death metal or power metal with ornaments to disguise complete lack of songwritting skill.
That's hardly metal
They could copy Norweign classics of yore without any of the spirit, they might be Cannibal Corpse with their second rate death metal selling out the once treasured genre, or maybe Pantera with grooves making up for substance.
Unfortunately, that is metal, although it's completely moronic.
What metal is, can be felt if you actually follow the music, it's the feel of it. Not as in, the sound of blastbeats, or distorted guitars. It's there in Sabbath, there in Maiden, there in Witchfinder, Morbid Angel, Carcass, Demilich, Hellhammer, Blind Guardian, Darkthrone and Sacramentum.
And no, the difference among them is not just aesthetic, as in types of vocals. The songwritting, and the phrasing are different, but they all hold a spirit that none of these newer bands have. So in conclusion, you ruined metal, go get AIDS.