Here is an interesting story that has gotten a lot of reaction.
First of all, the study does not show that "sexism in science doesn't exist." It is a bit more subtle and finely calibrated than this.
It studies a single point in the process: hiring. Actual hiring audits reveal that "women apply less often for academic jobs but when they do, they are more likely to be hired. For example, during 2002-2004, 20% of applicants in mathematics were women, but 32% of those offered the job were women." In other words, the sexism that does exist in science does not take the specific form of hiring discrimination.
In their study, Ceci and Williams did an experiment that found that scientists actually had a bias in favor of women candidates.
I have seen several objections to the story, but Ceci and Williams have answers to all of them.
Objection 1: The respondents to the study surmised that they were being tested for sexism and over-corrected.
Answer: They asked respondents to guess what the purpose of the experiment was, and nobody could.
Objection 2: The study overlooks discrimination at other career stages.
Answer: Yes, but it was targeting a specific stage in one's career, being hired.
Objection 3: But, sexism!
Answer: Yes, women are underrepresented in STEM fields. This underrepresentation, however, is not the result of explicit discrimination in hiring.
Objection 4: The women who survive graduate school are superstars, having survived a hostile sexist environment. There is still discrimination against mediocre women.
Answer: Maybe so, but if the women coming up are really superior, wouldn't that create an expectation that women are going to be better, on average? [This is my answer, not that of Ceci and Williams). That could explain the bias against men. On a search committee, I would look to the 20% of my applicants who are female rather than the 80% that are males, because it is more likely that I will find truly excellent candidates there. I don't understand the "discrimination against the mediocre" argument. Presumably a university wants to hire a power-house.
The main reason women are underrepresented is math, according to a study don at my own university. The more emphasis on math, the more attractive it is to boys who have great math skills and are weaker in verbal ability.