Twitter, the most popular microblogging platform on the Web, is five years old. But can it survive another five? I was invited onto Radio 4’s Today Programme with mydeco’s Brent Hoberman (co-founder of UK dotcom darling to talk about its future.

You can listen to the interview here.

Always a realist, I suggested Twitter wasn’t resistant to obsolescence. In fact, I said could go the way of the dodo. After all, it is a social medium, and if the crowd decides another service serves it better, they will inevitably flock away. It’s happened to other social networks in the past, most recently to MySpace and Bebo. It also happened to Friendster and Friends Reunited, as well as to online community based games like EverQuest.

The thing that gives systems like Twitter and Facebook (today’s digital media darlings) the edge over competitors is the social network that they have engaged. The social network provides the relevance that users demand. If that social network moves elsewhere, the value goes elsewhere too. Brent believes that Twitter has gone beyond the fickle social flock. Perhaps. I’m not convinced. It will be interesting to see what effect integrated advertising and their other proposed business model implementations will have on users’ perceptions of value.

Admittedly, Twitter is a slightly different beast than Facebook; the latter demands reciprocation, keeping relationships and online experience inward-looking, which makes it more susceptible to social fluctuations. Twitter, however, still retains some of the traditional media model: it can be used and consumed like a broadcast medium. But as soon as a critical mass of people who are considered valuable to an account holder move on, the service’s overall value reduces, and it becomes yesterday’s news.

In short, there’s nothing in Twitter’s essence that can protect it from future extinction. It is merely a microblogging platform. And although I use it incessantly (and have done since March 2007 – 4 years!), I know it could disappear. I’m prepared to move on when something that meets my needs better comes along.

And no, I have no idea what that new service might be.