Sources might be useful because many on LW will not be versed in gender socialization norms. These things make sense to me, but I can't say I've seen them explicitly stated before (at least in a way that stuck with me).
A bit later than intended, but here are some useful sources related to my post. I'd recommend the stereotype threat wikipedia article and the Handbook of Socialization as the best overviews for those less familiar to the topic.
Stereotype threat:
The Trouble with Bright Girls (article @ the Huffington Post)
Excerpt:
The topic of this article seems to relate to several common Less Wrong issues: the nature of human intelligence, and the gender imbalance among LW readers.
I'm not sure how much credence I give to the proposed explanation of the difference in mindsets. It may well have to do with socialization and feedback, but the specific description of feedback that is presented seems a bit too much of a "just-so story" to me. The difference itself is fascinating, though, and I hope more is done to further our understanding of it.