I think Blackwater park was a darker sounding album than deliverance AND better written/put together. Deliverance sounds too sterile to really give off that dark atmosphere that we relate to Opeth because of the way it was recorded. It also has one of the worst Opeth songs on it IMO which is, as you mentioned BTPISIO (albeit still good by normal standards) Don't get me wrong though, I love Wreath as a song and Deliverance & A fair judgement are classics. I guess Deliverance just wasn't as consistant as other releases.
Overall, I think Damnation as an album is a lot stronger release than Deliverance even though it strays from the normal Opeth formula by being entirely mellow.
I know what a lot of people mean about Ghost Reveries not sounding as dark though, this has a bit to do with Mike utilizing major chords a lot more on this release which adds a triumphant element to the music at times which is obviously not dark to the ears in itself, but taken in context of the song, I think it remains quite dark.
My hopes for the new album are that Mike expands on the more progressive ideas of Ghost Reveries while at the same time he goes darker than before adding a few more tradional Death/black metal elements alongside the more progressive side like maybe some blastbeats etc as somebody else mentioned..
So basically I want darker and heavier than ever but more progressive too :Smokin: