I get excited, not gonna lie. It's nice to know there's another girl in the game. The few I've come across also tend to be way less obnoxious than the other players.
As for others reactions to me, most of time they start by asking if I'm girl. If not, they apparently assume I'm a twelve year old boy and treat me as such, which can be fun sometimes when I prove them wrong. I haven't gotten any sexist comments yet, although one guy in Halo did offer to be my "knight shining red armor". Another player, who was probably pretty young, talked my ear off, telling me all about the sports he played and all the black belts he had in every martial arts known to man, etc. which was kinda cute at first, but I eventually had to mute him before I blew his virtual head off.