I know gender inequality hasn't gone away, and that we are not living in a post-sexist society, but I can still be caught by surprise.
For example, women buy and read the majority of books, but get the mouse's share of book review coverage .
Women have opinions, but some 80% of published op/ed pieces have male names in the bylines .
And now the New York Times has called attention to a survey that suggests over 85% of contributors to Wikipedia are men .
Wikipedia, to its credit, wants to do something about it. Sue Gardner, executive director of the Wikipedia Foundation, see it not as a problem of inequity, but rather a problem of quality. If a vast percentage of the world is not contributing, if their perspectives, interests, and experiences are omitted, Wikipedia will be less than it could be.
The effect can be clearly demonstrated without departing from a Wikipedian "neutral point of view" strategy. The New York Times story points out several situations in which articles about notable women or popular culture issues of greater interest to women than men are covered in far less detail than other topics. A Wikipedia editor who goes by the moniker Headbomb analyzed articles  on people included in a "science hall of fame" and found that articles on women scientists tended to be skimpier than those on men, and further found that the difference in biographical coverage was even more pronounced in areas where there was less of a gender gap. The more we're there, the more invisible we are. Kudos to the Wikimedia Foundation for identifying this issue and attempting to address it.
Since the New York Times covered the issue, I've heard more stories than I can count of women who gave up contributing because their material was edited out, almost always because it was deemed insufficiently significant. It's hard to imagine a more insulting rejection, considering the massive amounts of detail provided on gaming, television shows, and arcane bits of military history.
The responses to various commentaries on the topic propose different reasons for the gender imbalance. They tend to fall into these categories:
Many women say they don't contribute because they are too busy.
Many Wikipedians say anyone can contribute, so women are to blame if they don't contribute more.
Some suggest that men are more geeky and obsessed with facts than women, so writing Wikipedia articles is simply more fun for them.
Some suggest that women are not assertive enough and are too prone to undercut themselves. They need assertiveness training.
Some find that women are more often uncomfortable with conflict than men and shy away from electronic forums where they might encounter it.
Some suggest our brains are wired differently and men like staring at screens more than women.
A very large number say any complaints about gender balance are coming from politically correct, whining, sexist liberals who are trying to impose censorship on the most perfect form of democracy. So shut up.
I'm not sure what the underlying causes are, but when an information source that is consulted by countless information-seekers daily has such demonstrable biases, we have a problem. And when so many people deny we have a problem . . . well, that's a problem, too.