It's funny, but I see that slight change in topic to be really relevant (regarding "girl musicians = win"). If I'd said "Man, boys who play guitar are cuuuute," I doubt anyone would have noticed. Cute does not necessarily mean cutesy - nobody would have assumed I meant "like a puppy or maybe a baby, d'awwww." Either way, I didn't read anything into Sean's post other than "girl musicians are cool, rock on." I don't really see why there's anything wrong with that, and honestly the biting response to it seems a good example of reverse sexism.
Khar, regarding your multiple-choice from wayy back in the thread, what DO you think women are generally into (I don't mean this to be a leading question, I'm just trying to think of what genres girls tend to lean toward)? Most girls I know listen to "rock" music if you can call it that (well, whatever's on the radio, but that's what most men seem to listen to also) and a good bit of urban/R&B. I'll agree, though, that there are more males than females who tend to listen to metal, and possibly that's because metal does seem to have a bit more testosterone to it, so to speak. However, I know an extraordinarily large number of women who love female-fronted metal bands like Edenbridge and Within Temptation. I on the other hand prefer male vocals; I'm not anti-female-vocalist, I just don't tend to listen to them as much.
However, as you said, things have definitely changed over the years. Whereas ten years ago I'd be one of the very few females at a metal concert, it seems to be more evenly mixed now (though far from 50/50). As far as female musicians being a novelty, I don't really remember a lot of people going nuts over the fact that White Zombie had a female bassist, even after they became pretty mainstream. It was cool, but not shocking. So I don't know, maybe it's partly a difference in the people we interact with.