There are now more than 1 million social network sites. Some may hear that and think, "Wow, a million+ Facebook- and MySpace-type sites?!" Well, sorta. What Mashable's actually reporting on with that figure is Ning's explosive growth. In the fewer than four years since Ning's launch, more than a million mini-MySpaces have sprung up on its network. These are smaller, more narrow-interest social … [Read more...] about Zillions of social network sites