Not sure what to make of it yet. I really loved their first one, kind of liked the 2nd one, loved the 3rd one, and have no idea what to think on this new one yet.
Black Metal is much darker and usually rather abrasive, (though there are a ton of ambient black metal bands out there that are actually fairly mellow, though not neccesarily pleasant), almost a sort of proto-thrash with a real lo-fi production and harsh vocals . To give you an idea of the darkness of some BM, there's actually a sub-genre of it that's been coined "depressive/suicidal" BM.
Here's a few examples. You don't have to listen to the whole songs. Just giving you taste of the some of the variations within the genre.
The ambient kind
The Axis Of Perdition - The Elevator Beneath The Valve
http://www.youtube.com/watch?v=Pee-_YB-f_sThe suicidal variety
Xasthur (pronounced Za-Sir) - Screaming At Forgotten Fears
http://www.youtube.com/watch?v=6YedXRq3Pbo&feature=related Here's the Up With People type lyrics..
A sinister telepathy is screaming at forgotten fears
An exit made of your self-destruction, may your reflection guide the blade.
In your lost code of self knowledge, a mere entrance for evil to enter
The venom is hidden and the venom wears a mask (I serve myself upon the wings
of pains affliction, unto thee). Disconnect from my state of being (and
without a trace) it was my soul that murdered yours. the blistering kind
Craft - Fuck The Universe
http://www.youtube.com/watch?v=7_p1WBk9y6cAnd lastly, the "all over the place" variety
Deathspell Omega - A Chore For The Lost (it took me forever to get into these guys. It's seems like pure chaos at times, but repeated listens reveals something new each time. Now I think they're best example of the genre. They pack so many things into each song, and I love how the various instruments almost seem to weave in and out at times. An incredibly hard listen at first, but very rewarding, at least to crazies like me)
http://www.youtube.com/watch?v=dAGGFaogNVsLike I say, don't bother listening to the whole songs (unless you somehow end up liking it, of course. Good luck on that. ;) ).