An opinion offered by an actual woman in technology (eponymously known as "Jessica Boxer"; taken from a blog post I otherwise disagree with).
Firstly, I think the main reason women are less inclined to work in tech is because, as a general rule, women are much more sociable than men. I am sure you are aware of the good, evolutionary reasons why that is so. I believe this is more than a nurture thing, I think it is also to do with the way their brains are wired, which is notably different than the way men are wired. (This isn’t some handwavy opinion, it is a physiological fact.)
Because they are more social, they tend to want to do things that involve sociability more. The scientist or programmer tends to be a lone wolf, spending most of his time talking to his computer or test tube, rather than interacting with people. This fits in considerably less well with the preferences of women. it is also why women who are in computing tend to drift toward the more social jobs, such as testing, tech support, management and GUI design.
Secondly, because computing has tended to be dominated by males, the systems and processes that are in place tend to be more male oriented. for example, design meetings tend to be confrontational rather than consensus oriented, aesthetic is eschewed for functional, individual preferred to group. None of these are intrinsic properties of programming, neither are death marches for that matter. But the dominant class has set the system to their preferences, and so there is a feedback loop that decreases the attractiveness of programming to the less dominant group.
