From the '80s until today, BBSs, the usenet, mailing lists, and other online interest groups have been overwhelmingly male. Myspace was the first large forum to achieve a high female/male ratio. The key ingredients seem to be: 1. photographs to identify correspondents (rather than addresses) 2. reciprocal relationships - women don't want anybody to be able to contact them 3. many:many conversations (such wall posts)