Even when I haven't been involved in running an online community, I've always been a participant in several of them. And yes, some women need to feel "safe" before they will come out of lurkerMode. (Obviously I am not in that set, but I expect the woman who wrote the blog post to which I linked does count herself among them.) For instance, I'm a member of two women-in-IT tech groups (a general one and one specifically for web designers/developers, and believe me, you can't shut them up). The whole notion of women-in-IT and its reflection in online communities isn't going to go away just because some guys (and some women, too) say, "But really, you don't need a separate space."
(As you can probably tell, this is a topic very close to my heart.)