It may be too early to tell, but this may be my favorite Opeth album, as a whole. I kind of feel the opposite of Elysian Blaze: not every song may be totally outstanding, but together they just "clicked" for me. (Blackwater Park had nothing but great songs, but it was a bit too much all together.) As for By the Pain I See in Others, that's easily one of their greatest songs yet. It makes perfect sense to me. As an opener, I think Wreath is pretty awesome, though I'm not really sure yet how it compares to Advent, The Moor or The Leper Affinity. They are all excellent.
(I've been a fan since Still Life, so I'm a comparatively "new" fan, but not quite from the new wave of Blackwater Park bandwagonmembers.)