Check out the unofficial Ulver forum here at UM, I've been known to post there, and my good buddy Russell always has some great insight to them as well.
William Blake scares me, but I love it. Long, drawn out, and overdone, but awesome. Masturbatory music at its finest.
Metamorphosis EP is my least favorite (too trance/dance for me), but has one of my favorite songs, Of Wolves and Withdrawal.
Perdition City will receive a 10/10 from me within a year or two (CDs must be in my collection for several years before I can grant them this honor... some very rare exceptions though).
The Silence EPs are not for everyone, but they sure are for me, I absolutely adore them. If you're looking for something more ambient than Perdition City, but not quiet minimalist like Lyckantropen, here ya go. Good luck finding them, unfortunately they are of very limited pressing.
Lyckantropen is great except the last track... the only not-so-great song they have done. Very minimalist, this is definitely a headphones album.
I have heard one song from their forthcoming EP, it sounds like Future Sound Of London to me, which is just fine since I'm a huge fan of them as well.