I always wonder about having too many single-band forums. There's the risk that they degenerate into:
"I like Metallica" (or any other band you care to name)
"Yes, I like Metallica too"
"Hey, I like Metallica more than you do"
"Oh no you don't. No one's as big a fan of Metallica as I am"
and so on. Here, I think the balance is about right - plenty of TG topics but some scope to talk more generally. Hopefully every forum is built like that, but I must say that I've grown tired of a few - the offical Nightwish forum, for example.
I haven't yet found a single-band forum on which people are prepared to open up the full dimensions of the possible debate. Fan contributions tend to be just that - you don't get many people who'll actually come along and say "Look, this band is just mediocre. It's tolerable, but there must be 1000 other bands just like it" - or far, far worse. In TG's case, either this means that everything the band do is truly exceptional, or the other people wouldn't be interested in joining or posting anyway - or our old friend PHM is busy elsewhere.