CodeIgniter.com: CodeIgniter 2.0.0 Released
Today EllisLab and the CodeIgniter Reactor Engineers are proud to announce the first official release of CodeIgniter 2.0.0, which is being released in two flavors.
The "Core" version will be the branch that EllisLab uses for their internal applications and will be a bit slower moving. The "Reactor" branch, however, is more community-powered and headed up by a set of Engineers that will guide the framework and work to make it its best. Also mentioned as new in the post are the upcoming ability for users to contribute directly to the user guide, the creation of a standardized Authentication library and a more object-like model setup. If you're interested in the Reactor branch and want to try it out or contribute, head over to the bitbucket account for the project.