Man, I know we've laughed this post off already but I feel COMPELLED to say something about how misguided dock is. Is Steam's presentation "masculine"? Sure. But so is every sports
anything ever, and that sure doesn't stop millions of women from being fans. Dark colors, squared-off shapes or an overall "masculine look" aren't what put me off about venturing into male-dominated spaces like comic shops, conventions and "hardcore" (ugh) gaming. It's the creepy assholes therein creating an atmosphere of hostility, or even danger.
But you literally do not ever have to interact with another person in order to use Steam, so there's nothing to be put off by. Unless you're unused to navigating complex interfaces on a computer. Now
that would be something to be concerned about as a developer, because Steam's complexity and the level of technical skill required to use it
are barriers to mainstream adoption.
...But frankly, I don't think it's possible to drop the barrier to entry that low without creating a closed system. (It'll be interesting to see how Win8 turns out.)