Royal Pingdom has released some interesting stats on the users of 19 social networking sites (Facebook, LinkedIn, MySpace, Twitter, Slashdot, Reddit, Digg, Delicious, StumbleUpon, FriendFeed, Last.fm, Friendster, LiveJournal, Hi5, Tagged, Ning, Xanga, Classmates.com, & Bebo).

There stats highlight how social networking – which many look at as “something for the kids” – is going a little gray, with the 35-44 year olds making up the largest group.

Average age varies widely by site, with Bebo and Myspace users on the young end, and Classmates & LinkedIn users at the other end:

Other highlights:

• The average social network user is 37 years old.
• LinkedIn, with its business focus, has a predictably high average user age; 44.
• The average Twitter user is 39 years old.
• The average Facebook user is 38 years old.
• The average MySpace user is 31 years old.
• Bebo has by far the youngest users, with an average age of 28.

While social networking is now dominated by middle aged users, older users are not using social networking sites to a large extent. According to Royal Pingdom, “This probably reflects general internet usage, but we suspect the difference is enhanced when it comes to the social media sphere where site usage tends to be more frequent and time-consuming than usual.”

It also represent an opportunity for companies to develop new types of social networking that are more suited to the needs and interests of older Internet users.