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Attack of the (Twitter) Clones

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By Douglas MacMillan

Attack of the (Twitter) Clones

Twitter owes much of its popularity to simplicity. "What are you doing?" the site asks, letting users post responses in 140 characters or less. The service has attracted more than 3.2 million users, according to directory site Twitdir.

Still, the site has no enduring model for generating revenue. Can Twitter stand the test of time—and competition? We may soon find out, thanks to a crop of microblogging services launched in the past year. From multimedia-friendly Pownce to enterprise-pitched Yammer, these sites revolve around the sharing of short messages like Twitter does. Each also tries to provide unique tools designed to help users enrich their messages. Many also have what they believe is a better plan for turning a profit.

Each slide includes unique visitor figures compiled by Web analytics site Compete. These figures do not directly reflect the number of registered users on a site because they also count nonregistered observers.