Leading article: Twitter crowd problems

More strange and wonderful news has emerged from the world of Twitter. An employee of the website has divulged that "racks of servers" are dedicated to cope with the Twitter traffic generated by a single user: the 16-year-old Canadian R&B singer Justin Bieber. "Beliebers", as Justin's fans are known, are said to eat up 3 per cent of the social networking website's resources. Justin has almost as many followers (5.1 million) as Barack Obama (5.3 million). Our own Twitter champ, Stephen Fry, is well back on 1.8 million.

Perhaps this will become the new gauge of celebrity success. It used to be the size of your trailer, or your backstage dressing room, or the number of times you appeared on the cover of magazines, that indicated whether you had made it or not. But maybe one day it will be the number of dedicated servers you have at Twitter HQ.

But the Beliebers do pose a potential problem. What if Justin's fanbase keeps on expanding and starts to crowd out the rest of the Twittersphere? The economics textbooks suggest that one way to ration a scarce common resource is through tax. So could there one day be a Twitter tax ("Twax")? Do not rule it out. And you know who to blame if it arrives.