Misbehaving passes on a report about girls and careers in technology:

Jacquelynne Eccles, a University of Michigan psychologist, says that girls steer away from careers in math, science and engineering because they view them as solitary pursuits: "In order to increase the number of women in science, we also need to make young women more interested in these fields, and that means making them aware that science is a social endeavor that involves working with and helping people."

The bigger question is why they view those fields that way. In this regard, I don't think pop culture helps a lot. Take almost any tv show or movie that portrays software developers - how common is the unwashed, unkempt, thick black glasses look? I see this with my daughter - her mom and I are both in software, and her perceptions of developers are more colored by pop culture portrayals than by her own home.