Well, the app was so good that 37signals announced today that they've purchased the app from Overcommitted, renamed it to Campfire for iPhone, and they're giving it away for free in the App Store.
According to the 37signals blog, the company was so impressed with Ember that they approached Overcommitted about purchasing it, and the developer was happy with the idea. A deal was cut, a few changes were made to the app, the app made it through the Apple vetting process, and as of yesterday, Ember is known as Campfire for iPhone.
If your team uses Campfire for collaboration and file sharing, be sure to grab Campfire for iPhone as soon as possible. The app works on devices running iOS 3.1.3 or later, although it is not optimized for iPad.