While not at an industry level, which I agree would be interesting analysis. There is some research indicating at the group level, in general, women do have a beneficial influence: http://www.sciencedaily.com/releases/2010/09/100930143339.ht...
But I think there are two aspects of including more women, or any other underrepresented group, in tech. One is what you mentioned in regard to pushing the state of the art, but the other is providing service to different sectors of the population.
If the primary thing you need as an entrepreneur is to understand the needs and wants of your audience, there's only so far I can go before it's at best a purely intellectual understanding. Same thing with small startups, if they are growing out of scratching my own itch, the lack of women means needs specific to them are much less likely to be addressed.