I've got several female friends who play WoW -- I'll have to see their reactions to this article, and to telling them that they're figments of my imagination
That said, there's a lot of capacity for trickery on the internet - men pretending to be women, women pretending to be men, or even more complex relationships. A person's gender really doesn't matter when talking online, unless (I would imagine) you're trying to have a conversation on really gender-specific stuff (like how men aren't allowed in the Ladies' Lounge). And at that level, it should be easy to figure out who's a real woman and who's faking. In games, I highly doubt it's important.