Well, I can say that when they were here in Vancouver with Children of Bodom, As I Lay Dying and God Forbid, they were pretty impressive. Chris offered up the weakest performance, but let's face it, compared to a highly edited, Beat Detected to Christ smokin' studio take rendered to absolute perfection, any live drum performance is going to seem off by comparison.
I will Agree on Will Adler, though...I think someone ought to call it quits, perhaps. John C. was a'ight. Served the songs well and had good timing and sense of meter. Mark Morton and Randy Blythe were certainly the highlights, though. Randy has really nailed the commercial aspect with the pitched screams and Mark's playing was tasty and understated.
That being said, yeah, I'd say they're slipping a bit. And yeah, one could say they're playing power chords for retards, but hey: All rock guitarists are, for the most part always have been and forever will be. Personally, that's the way I like it. When I feel cerebral, I listen to jazz or classical guitar.
As for an obligation to the fans...what fans are these you speak of? The group that claims they were "into them before they made it big man, back when they were still good," but no longer listen to them or support them in any real monetary way or the group of bandwagon jumping wankers who, in three short years, will look back and mock them and "feel embarassed" for having listened to them while they praise the current trend though they'll undoubtedly be doing the same thing with band X another three years down the road? LoG (and any other band in the modern era, for that matter) owe no one anything, in my opinion. There are very few bands still touring and doing this until retirement anymore and the number of bands who make it into this category seem to diminish with each passing decade. God forbid, soon music will be viewed as completely disposable and no one will be able to do it for a living.