A report by media ratings company, Nielson caused a stir in April when it suggested more users were leaving Twitter than joining it - the so-called "Twitter Quitters". At that rate of attrition, Neilson figured, Twitter would have a tough time reaching sufficient mass to remain viable.

The Twitterati has countered that Neilson's research doesn't factor in the growth of third party Twitter applications like Tweetie and TweetDeck. What looks like abandonment of Twitter, they argue, is in fact the reverse: an overabundance of interest, requiring more sophisticated platforms to effectively manage the mountain of new information Twitter provides.

From personal experience this makes sense. By the time you begin to follow more than 40 or 50 feeds it becomes necessary to migrate to a less linear platform than Twitter's vanilla offering and start arranging tweets in thematic groups. In my case I use TweetDeck to organize my feeds into separate columns tagged for  favorites, media, clients, brokerage, complex event processing and so on...

But this poses a bigger problem for those who are assiduously building a 'following' in the hope that it will give them a powerful direct line to their target market. If the majority of your followers are migrating to third party applications wherein they can relegate your tweets to the equivalent of a spam folder, who's to say any of your followers are following you at all? And if no one is following you, why should you continue to tweet? As it stands old-fashioned blogs do a better job of showing the author how many people are genuinely following them, and this should worry anyone priding themselves on how many Twitter followers they have built. Interestingly, the old currency of blog popularity - comments, direct messages, and reposts - apply equally in the Twitterverse. If you have a thousand follower but aren't seeing this kind of activity, I hate to tell you but you may be delivering a speech to an empty lecture hall.

"Hollow Follows" not Twitter Quitters are going to define the success of user engagement on Twitter going forward.