I was on three gender panels at WisCon this year. I learned several things from them (and from other WisCon discussion), but here are the two most prominent bits:
First: I'm still very enmeshed in the gender-binary paradigm. Unless I make a careful conscious effort, I default to thinking that there are exactly two genders.
Second, and somewhat relatedly: Even though I made a point of explicitly noting, during one of the panels, that gender identity and gender presentation are different things, I'm still bad at remembering that fact about individuals in some contexts.
In particular, if someone presents in a way that I interpret as strongly male- or female-gendered, then I tend to assume unthinkingly that their gender identity and their pronouns match my interpretation of their presentation. Of course I know, if I stop to think about it, that that's not always true. But even so, I easily forget.
This WisCon was the first time, for example, that I've met someone who looked clearly female to me but who goes by the pronoun “they.” (I don't know that person's gender identity.) And I have a couple of friends who I relatively recently learned are genderqueer, but I still sometimes forget that about them, because when I look at them I interpret their presentation as male or female.
One result of these thoughts (among several such results) is that I now want to add caveats to all my author-gender counts. When I'm looking at a table of contents for an anthology, for example, or at a list of award winners, I tend to assume that anyone with a commonly-gendered-in-English first name is of the gender usually associated with their name, even though I'm becoming increasingly aware of people for whom that's not true. It's an easy shorthand assumption; and there may be no way to find out the actual gender identity of many such people. (For example, there are plenty of past Hugo winners who are no longer alive.) So I'll probably continue to make that assumption for the purposes of counting authors by gender—but I'll try to remember to include disclaimers pointing out that I'm making that assumption, and offering to update numbers if someone corrects me.
Anyway. It's not that I'm Deeply Troubled by my reactions or anything; just that I think this stuff is important, and it's something for me to work on.
(Wrote most of this right after WisCon, but neglected to finish and post it 'til now.)