Opeth turning black metal = the end of their careers.
Opeth progressing to something new and evolved = the makings of a long fruitful one.
I understand that there are alot of you people who listen to Opeth because they are another heavy "death metal" band to listen to along with all the other "br00tal" bands you listen to, but in my 6 or so years following the band, I have found the heavier they get, the more boring and bland they get. Which led me to realize Opeth is not death metal, they arent extreme, they are different...Black metal isnt different, its old, and there are plenty of bands out there that are playing black metal just fine now...I wish Opeth would drop their stupid ties to the scene, and their dumb extreme metal stigma and just progress and evolve the way a great progressive rock band should.
The metal stuff was great and incredible and definately transcended the genre, but alas I think the band should just let that go, and discover new elements of music to incorporate into their style. Damnataion was a step in the right direction, albeit a small one...Id like to personally see the King Crimson/Camel side of Opeth show more in their overall compositions (as in "The Moor")