I guess it all depends.  At the company I'm currently working at (a mammoth firm with over 50,000 people globally) I, a Caucasian, am very much in the minority.  And there seem to be far more women than men in my office at every level of management and staff.  Some of it is an active attempt on the part of the company to pursue diversity, a lot of it is that the company has a strong referral system. 

 I have found that there are areas where there are fewer women (software development for example), but in general over the last 20 years or so, you do find a strong female workforce, including in management, at least here in Toronto.   I don't think it's essential for women to be as interested in software dev as men... just as there may be roles it's not essential for men to be interested in.  Vive la difference!