This is from 2006. I'm sure their fake name detection is much more sophisticated by now.
"Our automated system will not approve this name. If you believe this is an error, please contact us."
At least they let folks contact them now, I guess.
Don't bother saying "What if I check between their legs?" or anything like that, because gender and sex are two different things that are merely strongly correlated in most people.
I never said that was true in all cases. In fact, I said it was strongly correlated with gender in most cases. However, it isn't an absolute determinant, especially if you equate 'sex' with 'genitalia'.
Web sites that need to know how a person is physically constructed as opposed to socially constructed are going to be rare.
But even then, the physiology is not always always binary: "1 percent of live births exhibit some degree of sexual ambiguity.Between 0.1% and 0.2% of live births are ambiguous enough to become the subject of specialist medical attention" - http://en.wikipedia.org/wiki/Intersex#Prevalence
Look, EVERY website is built based on some assumptions. Sometimes it's that people comprehend a certain language. Sometimes it's that they're using a browser with support for images and they're not using LYNX. The general assumption of most websites is that their user hasn't changed their gender ... and while I'm sure there's some equal-rights group that would disagree with me, I think that's a fair assumption. I'd also bet that for the vast majority of sites that request gender information, that input is unlikely to ever have an impact on the user's experience on that site.
If a user has transformed their identity, then I think they've also taken on the responsibility of figuring out how that new identity will navigate the real-world. That means a woman that identifies as a man can enter "Male" in a gender drop-down if that's how they choose to self-identify, but unless they've had a surgical procedure to change their physiology, then they're still going to need to operate their body like any other woman would. If they're in a pharmacy, that means buying feminine products to maintain their body. If they're on WebMD, that may mean declaring themselves as a woman to get relevant content. If they're on a dating site, maybe it makes sense to declare themselves as a man ... much to the potential future chagrin of their date.