Thinking about starting a social networking site? You're so in luck. VentureBeat relays the shocking news today that the popularity of social networking sites is growing—and fast. While we could have told you that based on the amount of time we spent on Facebook alone this morning (er, sorry Boss), VB actually has some real data:

"Social networks are getting more popular on every continent in the world, except for North America, where they were already popular, a new comScore survey shows."

Whether that means the trend's close to peaking and the market's fully saturated, however, is not yet clear. But if you're looking to get a piece of the pie for yourself, here's who you're going after: