Twitter CEO Jack Dorsey said the service is working on upgrades including improved e-mail notifications, the ability to let users create groups of Twitter friends, new instant messaging and social media connectivity, and iPhone applications. However, they'll all have to wait on improving Twitters uptime, he said, which has recently been horrendous.InformationWeek did a one-on-one interview with Dorsey late Tuesday. He also described what Twitter is doing to improve uptime and Twitter's lack of a business model.

Dorsey declined to provide a timetable for the new capabilities, saying improved uptime is the company's main focus for now. focus for now.

One item on the to-do list for Twitter is to extend support for e-mail. Now, users can opt to receive direct, private messages by e-mail; Twitter wants to extend that so that users can receive all messages by e-mail, either individually or in digest form.

Another feature: Giving users the ability to group their Twitter friends, so users can send messages just to family, for instance, or solely to co-workers.

Twitter is planning to add new entry points to Twitter. It will connect to more instant message platforms and more social networks. The service currently connects to GTalk, LiveJournal and Jabber IM, and has plug-ins to connect to Facebook, blogs, and other social networks.

I asked whether Twitter might extend the 140-character limit on posts, Dorsey said that's not an option being considered; that limitation is fundamental to the system. The 140-character limit means that Twitter can reach "every technology without compromise," the recipient might be picking up messages on a cell phone in Kenya or on an advanced desktop computer, but the sender doesn't have to worry about that, Dorsey said. However, Twitter is working on more intelligent rendering of links that users send in tweets; for example, a message that includes a link to a YouTube video or Flickr image would also include an embedded player when displayed on the pages of the Twitter site.

Dorsey sees the API is a major advantage for Twitter, allowing third-party developers to build applications like Twhirl, Twitervision, and the iPhone Hahlo that allow users to display and send tweets in innovative ways. "Just providing the API has allowed us to move a lot faster. Anyone can take the system without telling us and build whatever viewpoints they wish, and send and receive updates that they like," Dorsey said.

Twitter is excited at the opportunity to develop native iPhone applications; the second-generation iPhone, with support for third-party applications, is due this month. It's rumored that the iPhone will include GPS capabilities, and the Twitter API includes capability for a user to send his location, which would allow iPhone users to geotag their Tweets, Dorsey said. He admires the way Apple is managing the application store, developers pay $99 for access to a software development kit, and Apple handles software distribution through iTunes. Combine that with Amazon S3 for storage and Google App Engine for running applicatons, and that means developers can focus on writing code and leave the infrastructure to others.

More to come on this interview.

Got any follow-up questions for Jack? Leave a message below and I'll try to get them answered.

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