LinkedIn 39, Facebook 33, Twitter 31, MySpace 26

For those who didn’t catch Twitter’s trending topics today, you might be curious about what these numbers mean. Anyone guessing median age?

That would be right! The numbers represent the median age of users on LinkedIn, Facebook, Twitter and MySpace.

Facebook is definitely aging as its median age increased from 26 in 2008 to 33 this year. We might have parents to blame for this!

Twitter is on the other hand, aging backward with 33% of users age between 18 to 29 year old, a significant increase from last year.

As you can see from the graph done by Pew Internet below, Twitter is attracting more Internet users from all age groups, particularly from the 18 to 34 group.

Oh Gen Y, why this sudden change of heart?

One big reason would be with more peers joining Twitter, young users see added incentive to use it for social networking. It’s very much a snowballing effect, which Facebook also faced before its user population exploded.

For the younger bunch, enthusiastic celebrities and companies, such as ASOS and Seventeen on Twitter are encouraging them to adopt and use it in their daily lives. Older of them are using Twitter to build their online profiles and social networks for work and business purposes.

Increasing adoption by schools and businesses are also catalyzing this trend as more people see value in Twitter.

With that said, would Twitter continue to age backward? It’s hard to say and it really depends on how big the younger age group would grow on Twitter. Currently, Twitter has very little when it comes to attracting the young ones.

This is especially so when it still has a lot of potential in the business user population. Social media in general is rising in the Asia market as more companies all over the world see value in it.