Pingdom has published an interesting study regarding the ages of internet social network (i.e. Facebook, Twitter etc.) users in the United States.
The average age is a lot higher than I thought. I would have guessed that most users are teenagers or college kids, but the largest group of users are actually from the 35-44 of age range. And I would never have thought that the average age for Twitter is close to 40 and ‘older’ than Facebook users.