yes I know this post is old, but i just registerd today and felt like adding my 2cents in here haha.
Ive read some people have said that old LP's sound was a mixture of Nu-Metal and Hip-Hop...in some ways it is true, but the genre itself "Nu-Metal" is in fact a blend of Heavy Metal, Hip-Hop, Alternative Metal etc all squished into 1 sound.
The whole Nu-Metal concept was created by Korn back in the early 90's. They were a heavy band, but with Hip-Hop grooves and beats added on it, so people didnt know what genre they can place them in, so they created a new genre for them called "Nu-Metal".
Going back on topic, I think the new album (even if i disagree with this decision) will keep going with its Electronica/Alternative sound like from ATS.