Currently in private beta, CoTweet is designed for companies and teams that need control over their use of Twitter as a brand. One of the big challenges of using Twitter as a team is that you are forced to share one login and you can't track who posted what Tweet.
This is a great idea and one that I am sure many companies would be willing to pay for the service, likely moreso if it had come from Twitter itself, instead of a third-party.
Trying to figure out Twitter's business model is a common parlor game here in the valley. It seems like everyone but Twitter themselves have figured out ways to (theoretically) monetize the service.
Check out the demo video:
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