I absolutely love satyricon. Old the most, but new as well. But, they couldn't get my honest vote. Neither can emperor, just for prometheus. I knew it was time to break up with my bf when I finally got him to listen to emperor, and that was the only album by them he liked. But yeah I love both of them a lot, just couldn't honestly vote for them because of the newer albums.
Burzum...Varg continued where he left off when he went to jail with Belus. Problem is, black metal has progressed so much since then that I find it hard to care about a new album that sounds old but really isn't. And really, poorly designed album artwork and layout should remain a thing of the past.
Mayhem...I like them a lot but I really only listen to deathcrush and DMDS.
So, I voted for Immortal. They are the only band, who I can honestly say I like all of their albums. I shat my pants a little when I found out they released a new album and went on tour. It could be argued that as a BM band, they've made the least progress and changed the least over the years...but really I think that's what I like about them a lot. That whenever they do something, I can expect it to be good old immortal.
And Darkthrone...I love this band, but there are so many albums that I find it hard to overlook the bad ones, even when the awesome ones are really awesome.