In report after report, companies like Apple, Google and Facebook all acknowledge that their workforces tilt heavily male. Silicon Valley companies are notoriously dominated by men, particularly in leadership roles and in jobs involving advanced technical skills. Men account for 7 in 10 workers at Twitter, for example.

Many of these companies have pledged to do better — and what's heartening about this is that efforts to improve gender diversity could also wind up accelerating other positive workforce trends: namely, closing the gap between men and women when it comes to wages. Data already suggests that the gender pay gap is less pronounced in tech than in some important fields. Meanwhile, women's wages as a percentage of men's have been gaining ground for years, not just in technology but across the economy as a whole. The gender pay gap in tech is still worrying, not least because the sector's become so vital to our national well-being. But it's a promising trajectory we're on.

Let's start with where we stand today. Research from the National Center for Education Statistics shows a significant gender pay gap for the country's most recent college grads. At this stage in people's careers, there's a 28 percent difference between women and men in computer science jobs and a 12 percent gender wage gap in engineering.

The pattern looks much the same four years after graduation, according to the White House (though it's unfortunate the data points aren't labeled).

But as problematic as the picture may look for women programmers, the gap is hardly as wide as it once was. According to Census data research from the Silicon Valley Index — a periodic survey of the Bay Area economy — men in 2010 with graduate or professional degrees made roughly double what their female peers did. In 2012, the Silicon Valley Index found, men were making just 73 percent more than women — still a big disparity, but a markedly smaller one than before. That trend is also reflected nationally; although the gender pay gap widens as workers grow older, what women make on a weekly basis has risen faster over time compared to men.

The Silicon Valley Index figures aren't broken down by occupation, or by tech versus non-tech. Still, there are other promising signs. Harvard University scholar Claudia Golding recently looked at data showing that compared to other fields, women tech workers are doing relatively well.

(Claudia Goldin, New York Times)

Goldin's research covers tech workers not just in the technology industry per se but in all industries — such as manufacturing, where computer software has become a vital component in aircraft and automobiles. But, she said in an interview, it wouldn't be surprising if Silicon Valley's growing attention to gender diversity results in a bidding war for female workers, driving wages up and narrowing the gap even further.

"If you have enough pressure, then you'll cause this race for the talent that's out there," said Goldin, "or in some cases, certain talent that has been overlooked."

One way this could happen is through stronger recruiting efforts on college campuses. There's already a cottage industry of tech recruiters who parachute in to "do their song and dance" for qualified candidates, as Goldin put it. By reaching out more intensively to women and minorities, companies would widen the talent pipeline for these groups.

"All those companies having published the fact that in the core technical jobs they have an under representation of women," said Ariane Hegewisch, study director at the Washington-based Institute for Women's Policy Research, "it makes a lot of sense that they are now trying to say, 'Let's get more women.'"

All of this paints a surprisingly progressive picture for Silicon Valley, which has been dogged by accusations of sexism and and a male-dominated monoculture. We still have some work to do, as LinkedIn put it. But the relative rarity of women in tech could soon become a point of leverage in demanding equal pay.