The very popular iPhone app, Tweetie by Atebits (the Loren Brichter’s company) has been purchased by Twitter, the service it’s a client for.
Twitter decided to buy instead of recreate its own mobile client, so it settled on Tweetie. It rename the app to “Twitter for iPhone” and then make it free in the iTunes App Store.
Loren Brichter will join Twitter as a key member of their mobile team.
This has been confirmed by Evan William, one of the founder of Twitter, on their blog.