I’m glad to see some more discussion of the gender situation in philosophy discussed more widely. It started with an article in The Philosopher’s Magazine, “Where are all the women?” which was then picked up in “A dearth of women philosophers” in the NYT. There are some interesting responses on Feminist Philosophers blog (first, second, third post), on Edge of the American West, on Knowledge and Experience, and mentioned on Leiter’s blog.
For background data (not in philosophy, but in science and engineering) on research on gender differences in aptitude, patters and mechanisms of discrimination, trends, etc., I can only recommend again the definitive report of the National Academies’ Committee on Maximizing the Potential of Women in Academic Science and Engineering from 2007:
as well as a new report (2009):
It’s instructive to compare philosophy to mathematics: roughly the same numbers, but in mathematics it has been improving (31% women math PhDs in 2008 vs 24% 10 years earlier) while in philosophy the numbers have remained around 28% for a while.