“Twitter is a Fad,” says BusinessWeek.com:

Like you really needed me to tell you this? Yes, you can follow me and several of my BusinessWeek colleagues on Twitter. And I’ll be the first to say that I like Twitter — it’s fun and useful finding out what friends, coworkers, and industry big-shots are reading and thinking. I also like hearing about how marketers are leveraging the technology, and it’s amusing to follow celebrities.

But Twitter is still a fad, and according to a study out today, it looks like it’s popularity may soon fade. Conducted by Nielsen Online, it focuses on “Twitter Quitters,” people who start a Twitter account but then fail to return the next month. Twitter, the study points out, has a very low retention rate, just 40%. Unless it figures out how to get more people to stick around, that means Twitter won’t ever achieve sizable reach online. “There simply aren’t enough new users to make up for defecting ones after a certain point,” writes David Martin, VP of Primary Research at Nielsen Online. With its current retention rate, Martin calculates the service could never reach more than 10% of the Internet population, even in a best-case scenario. […]