Damnation will be the pinnacle of Opeth's career in music. It is by no means selling out, unless the masses suddenly find themselves able to digest complex, non-repetetive popcrap and embrace talent, artistry, and itegrity (my three favourite buzzwords).
Even if Opeth starts to show up on the radio and TV, I'd know in my heart of hearts that the music they created was pure, and that the subsequent success is merely a reflection of that purity, not the reason for its creation.
I have no doubt that Opeth will have more "METAL" albums after D2, but I feel that their style will take several more changes before the Opeth legacy is complete.
And I'll be in line to get every album first, dammit.
NP: Kansas - Dust in the Wind