I'm -1 on asking folks their gender, and can happily consider a more obviously neutral term. Ubuntero wasn't supposed to be gender-specific, but for many people it will feel that way, and it seems silly to keep ourselves in a position where we have to explain that all the time.
I think the "Ubuntero" designation is given to people who've signed the Ubuntu Code of Conduct in LP. There have been some suggestions, with the number of upstreams adopting LP (and other distros) that we should move to a General Code of Conduct which is more relevant for a broad cross-section of communities. Membership in Ubuntu-related teams is already conveyed through the use of team badges on a person's page. What do folks think of that idea?