There are millions of Twitter users, but the number of application developers supporting the microblogging platform isn't too shabby, either.
In an inaugural e-mail newsletter detailing the company's progress, Twitter co-founder Biz Stone said some 70,000 registered applications have been created for the platform. Third-party applications do everything from helping users manage their Twitter accounts and lists of followers to finding discussion groups and videos on specific topics.
While often dinged in industry circles for not having a revenue model, Twitter continues to expand as a company: Stone said in his e-mail that registered user accounts have grown more than 1,500 percent while Twitter's number of employees have grown 500 percent.
Company officials have indicated they plan to introduce advertising and other potential revenue streams.
In the meantime, though, Twitter is focusing heavily on its developer community. Stone said the company will hold its first conference next month. The first Chirp conference for Twitter developersis set for April 14-15 in San Francisco.
Recapping the past year, Stone also noted several features that have been added to Twitter, including "the ability to create lists, quickly spread information with a retweet button, and an easier way to activate your mobile phone to work with Twitter over SMS. We also built a new mobile Web site that looks and works much better on smartphones."
Stone also said that Twitter had "a little dance party" to celebrate the hiring of its 140th employee: "His name is Aaron and he's an engineer focused on building internal tools to help promote productivity, communication, and support within our company."
Twitter's hyper-growth has not been without a few bumps along the way as the service has had to weather service outages and security attacks.
Stone didn't touch on those issues in his e-mail, but he did highlight how Twitter has been used in crisis situations to inform and aid people in need. Tweets are frequently cited by news organization looking to get the latest information from crisis flashpoints like the earthquake in Haiti and demonstrations in Iran.
"By working together during critical times when others needed help, sharing important information that otherwise might not make the news, and inventing new and interesting ways to use Twitter, you've shown us that Twitter is more than a triumph of technology -- it is a triumph of humanity," Stone said. "Projects like Fledgling and Hope140were inspired by you."