It's a bit heavier than normal (my tastes have changed), but these guys are amazing. I hadn't heard of them before, and when I got the album on promo from Century Media, I was in for a more-than-pleasant surprise.
Borknagar is coming out with a new album, and it's an extremely mature album, IMO. Avant-garde, heavy metal. 3 singers, elements from a wide array of music.
The album, "Urd," is coming out soon. I did an interview with Oystein, the lead composer of the band, because I fell in love with the album so much. Every single song is 100% different.
Their promo track, "Roots," is a bit heavier, but if you're willing, listen through until the end. It's worth it.