According to a Media Post article, MySpace ruled the U.S. social networking space in terms of sheer volume, receiving more than three-quarters of all the social networking traffic in the U.S. in 2007.

Facebook took the number two spot–snagging nearly 13% of all social net traffic, followed by Bebo with about 1%. But all you Facebook lovers should be happy because traffic to MySpace was actually down by 8% from the previous year. In contrast, traffic to Facebook was up by some 51%.

Researching age demographics for Myspace vs. Facebook provided me with no good recent reports on the age differences, though I found a great one from 2006 about how 68% of Myspace users are over 25.

According to Quantcast, Facebook’s demographics leaned heavier to 18-24 (54% are 18-24) where as MySpace’s demographics were spread out a little more (38% are 18-24 and 22% are 25-34).