Metal is an ever-turning and twisting genre, following wormholes into subgenres and melding any and all techniques and sounds along the way in a constant struggle to create something new and original. It doesn't always work, and anyone who lived through the '90s can attest that the addition of hip-hop elements like rapping and turntables was a serious low point.
Except now we have a whole generation who grew up on that music and wants to give it another whirl. You can find bands like Whitechapel and Suicide Silence admitting how much their sound is indebted to Korn and Slipknot, while others are even busting out those turntables again.
There's a difference this time though. Insane as it may sound to say it, it's working this time.