Opeth has eleven years and eight amazing albums to its credit.
From the 1995 release of Orchid to the "major label" release of Ghost Reveries, Opeth has continued down a path the band has paved. Contrary to the belief of some that going mainstream (if that's what they are considered on the Roadrunner label) is somehow the culmination of Opeth is nonsense in the fact that Ghost Reveries was written before they ever signed onto the label. And I'm sorry to report that Opeth is anything but mainstream. You don't see them filling an 18,000 seat stadium, which to me is an important sign of being mainstream.
A listener of music, and more specifically the follower of a band, has a some mental choices to make. Has your journey been satisfying? Is the band fulfilling your image of what they should be? Is the band being true to itself? Well, in my estimation Opeth HAS been true to itself. In reading various articles and interviews, Opeth has delivered eight albums of their creation. The new album has my all-time favorite song on it - Ghost of Perdition. When Kashmir was released by Led Zeppelin, that was my all-time favorite song. It took 30 years for a song to kncok Kashmir out of my #1 spot, and that song was The Drapery Falls. Five years later, The Drapery Falls has fallen to second place. I guess that means to me Opeth is still producing ever so powerful and under appreciated music. For me, Opeth doesn't get the musically genious credit it deserves. Whether it's the growls or just the genre, they just haven't been given the chance to dance in the big show. It's a shame, but the metal genre keeps most bands relatively obscure. Metallica most definately broke the metal mold, but not many metal bands have followed, at least not to that level. Opeth deserves more - their music is brilliant.
I've grown tired of bands over the years after being "stuck" on them. Aerosmith didn't grip me their entire career. Nor did The Beatles, The Rolling Stones, Black Sabbath, Metallica etc etc. There are only two bands that have never lost their grip on me - Led Zeppelin and Opeth. I'd also say Grip Inc. but only three albums doesn't put them in my legendary status.
If you feel Opeth is "done", there is a ton of music out there waiting for new ears. Nothing wrong with moving on, or having a certain sound grow old. It just hasn't happened to me with Opeth. I just don't grow fatigued of them, nor do I feel they've tapped themselves. If Ghost Reveries is their last album, no regrets here. They've left me with plenty of memorable music. But until that day comes, I will just listen and anticipate their future until otherwise noted.