This is a topic I've given a lot of thought to over the years.
My RL gender is no secret. It's in my profile's 1L tab. (Ask anyone who met me at SLCC.) Experience has taught me that it's better in the long run to practice full disclosure when the situation requires it.
I present cross-gender in
SL to satisfy my curiosity and to have fun. At the same time, I try hard not to give in to the usual male-fantasy foolishness that a lot of guys do when using a female avatar. While I try to behave the way I believe an RL woman would, usually I'm just myself. I've learned quite a bit by sticking to that policy.
In my opinion, online interactions among people have a long way to go before we can really learn to divorce what's online from what's physical. I see it as a generational issue. As more people grow up steeped in internet culture, the difficulty of online identity versus physical identity will lessen.
Mind you, I don't go around in-world wearing a prim sign with "GUY" written on it. If J. Random Avatar doesn't read my profile, well...
I can only do so much. If I become friends with somebody and the topic of identity comes up, I deal with it then.
If today I entered into an intimate relationship with someone in-world, I would make every effort to be honest with them about my RL self. I feel it's less painful that way. Some people don't want to know that information; I'm OK with that too. I don't know how I'd handle intimacy issues with someone willfully ignorant of my RL self, since I've never been there. My experimental cybering days are behind me anyway, so I (hopefully) don't have to worry about it.
On the flip side, full disclosure shuts some doors, too. The example of the "fauxbian" trolling some womens' hangouts in-world struck a chord with me. While I have enough self-confidence to not identify with that particular stereotype, I also don't want to make others uncomfortable. I realize that some are disturbed simply knowing "OMG, that's really a guy, what's he doing here?" so I err on the side of caution and avoid those areas.
Life is overly complicated sometimes, isn't it?
(Apologies if this seems rambling. I took like an hour to write this so I didn't have a wall-o-text.
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