Thunderstone: I'm not offended if someone uses male pronouns to refer to me as online, and sometimes I don't bother to make the correction. I may be a lady, but I understand that unless you ask or just know someone you can't know. I think
most people are reasonable enough not to overreact.
Yep, this is exactly what I was thinking. My avatar is a fishman, my username is used by both genders, depending on the country. I am not upset if I am addressed with the wrong pronoun. How could you know?
A lot of usernames don't make it clear if someone is male or female, and that's fine by me. I just avoid using pronouns when I don't know. The ambiguity is understandable too, since most reasonable people would like to be known for their thoughts and actions alone, not judged by any gender bias.