I mostly play girl characters
When I play video games - from Street Fighter to Guitar Hero - I tend to have a female avatar. I really noticed it again when my son commented on it while watching me rock out (yes, dammit, rock out) with Guitar Hero.
"Why do you always play as girls?"
It's odd, because when I started in Second Life I did not hesitate to choose a male character, with slightly long hair, a little overweight, and with a goatee... wait... my avatar looks a lot like me. The thought of having a female avatar really bothers me there (though I'll probably eventually have an androgynous one just to visualize a character in a story of mine). Second Life - even more so than other online MMPORGs - allows for people to be whomever they want to be. However they want to be. With a minimum amount of effort, I can already transform myself into anything from a hippo to a Matrix-looking ripped man; a female paralegal imp to a six legged ... thing. Vampires and were-creatures, furries and ghosts all roam the virtual world.
And there's sex. User only knows how all these different ... bits... work together.
In "How Men Have (A) Sex", John Stoltenberg deconstructs the idea of our sex as group identity. He points out how being male is a collection of behaviors, not necessarily linked to each other - and how trying to tie them all together is problematic at best. He makes the exquisite point that a penis does not the male sex make, and how there's a continuum from end to end of the spectrum. I have to quibble a bit with this - the spectrum of gender cannot be quite as uniform a spectrum as he posits.
Pressures from the environment would keep the less-polarized behaviors from being dominant (even if they're still there, they wouldn't be exclusively exhibited). However, as the pressure comes off, then you'd start to predict an increasing number of people claiming somewhere in the middle. And that's exactly what you see in Second Life, as the social constraints and pressures are removed. It's another layer on top of the socialization layer on top of the biological layer. (I say that because sexual norms and morés are still exhibited in accordance with our society in places - it's just *who* is displaying them that's changed. Still, this is a step in the right direction in moving towards a postmodern sensibility towards gender.
There's also some "nuts and bolts" advice about sex - which is basically good stuff. I'm actually surprised this stuff has to be spelled out (which may, itself, explain a lot): consent, mutuality, and respect are absolutely essential. I've known people where the other person had so many hangups about sex that it required - required - them to be have alcohol to engage in sex. At that point, however, they became extremely sexually aggressive - and the whipsaw shift startled both of us no matter how often it happened.