There is a tax that I pay for being a woman in computational science. Compared to my (majority) male colleagues, I am disproportionately called upon to do outreach activities and participate in photo shoots. So I can relate to what Female Science Professor is talking about when she seeks "diversity help." Although I've never been explicitly asked to do something for the sake of diversity, it has always been implicit in the invitation.
Many of my fellow "diverse" colleagues (and this group includes not just women, but African-American, Hispanic, and Native American men as well) resent this tax upon their time. I can see where they're coming from. After all, while I'm out talking to middle schoolers, all the dudez are actually getting some work done. It's true, we have to do these types of outreach activities on a volunteer basis -- we get no credit at work for helping to mold the minds of the next generation. Management loves that we do it, as long as it doesn't interfere with the day job.
I think this is a shame. And when I am in management, I will work to change that attitude and actually provide some concrete means of crediting those who go out and make a difference in the community.
In the meantime, though, I see the need for those of us who are not stereotypical scientists to do outreach. I don't let it take over my life, but I do enjoy speaking at middle schools and giving machine room tours to young people, especially girls. It is every citizen's duty to give something back to society, and I'm glad that I can contribute by being a role model for the next generation of scientists, and help make science that much more inviting to those who don't fit the stereotypes.