As any serial conference-goer can tell you, the conversations that occur outside the scheduled panels and sessions offer equally compelling opportunities for learning and discovery. This was perhaps even more true at this week's Fortune Brainstorm Tech conference due to the broad spectrum of attendees from the wide world of technology.

On Tuesday evening, during an uncharacteristically clear sunset over Half Moon Bay, I met Dina Kaplan, co-founder and COO of blip.tv, a video-sharing site. Kaplan was gushing over the abundance of women here compared to other tech conferences where she was only one of a handful. I counted over 70 women, and their presence on panels and leading sessions has been key - from Lynda Clarizio, president of Platform-A and EVP at AOL (TWX), to Facebook president Sheryl Sandberg to Marissa Mayer, who heads search products and user experience at Google (GOOG).

The discussion at dinner turned to women, as one software industry veteran claimed to have witnessed an exodus of women from tech starting in the early 90s. The Internet bubble reversed the trend temporarily, but once again women seem to be disappearing from the Valley. He posited that this is due to a harsher work environment in tech overall, and the impact is greatest on women. Diane Greene, one of the few women in tech on our Most Powerful Women in Business list, was recently dethroned as CEO of VMware. Coincidence or trend? The New York Times reported this week that, for the first time since the women's movement, the percentage of women in the workforce has fallen following a period of economic recovery.

Another fascinating gender trend in this virtual world: More men, Rosedale says, choose to live as women than vice versa. If women have the power in the virtual world, no wonder men want to be women. - Jessica Shambora