AstroGeek saidProud nerd here! To me it means I'm into science and computers. Also that I can be a little socially awkward. If you find the XKCD or SMBC web-comics funny then you're probably a nerd.
That's more or less along the lines of what I was thinking. Generally, people seem to think that because they watch cartoons or play video games it makes them a nerd. I don't think someone who truly is a nerd would go out of their way to make that claim. It seems like they toss the word in their profile because it makes them seem different or to add to their appeal and I just don't get it.
"A nerd (adjective: nerdy) is a person, typically described as being overly intellectual, obsessive, or socially impaired. They may spend inordinate amounts of time on unpopular, obscure, or non-mainstream activities, which are generally either highly technical or relating to topics of fiction or fantasy, to the exclusion of more mainstream activities. Additionally, many nerds are described as being shy, quirky, and unattractive, and may have difficulty participating in, or even following, sports. "Nerd" is a derogatory, stereotypical term, but as with other pejoratives, it has been reclaimed and redefined by some as a term of pride and group identity."