the metalcore scene?

Just want to point out that Metalcore is not a genre, it's a scene.

There is a big 4 of this scene, just like thrash. That being Shadows Fall, Killswitch Engage, Lamb of God and God Forbid. In addition to those bands, other bands that fit the scene are As I Lay Dying, Beyond the Embrace, Avenged Sevenfold, Chimaira, Unearth and Trivium.

I haven't heard All Out War, Atreyu or Caliban. Gives me new stuff to check out.

With that said, I ABSOLUTELY love this scene, with the exception of the annoying slam-dancing hardcore fans... god they piss me off. But anyway. For the most part, the melody is there and the agression that I like about thrash is there. It's different. Modern American Metal is a good way to describe it. Influences come from all over the place. Shadows Fall definitely draws heavily from thrash. Avenged Sevenfold has a little more punk in it. Lamb of God is more hardcore than any of the other ones. Etc etc etc. Absolutely awesome.

Killswitch's new album comes out in May. You can download the unmastered promo on any P2P program. It's called The End of Heartache. It kicks some serious ass.

As for Biohazard, their older stuff is much better. And yes, Danny Schuler is a kickass drummer, not to mention an awesome guy. (I hate to brag but) Him and Billy (the guitarist) produced my band's EP. They did an awesome job, and were very very cool about it. As for where you place them, they're one of those bands that really doesn't fall in any genre but metal. They're rap-metal-core maybe.