CodeIgniter 3.0.0 has been released, and is now available for download 
Changes compared to CodeIgniter 2:
Here are some instructions for upgrading to CodeIgniter 3 from CodeIgniter 2.
Many, many thanks to @narf for shepherding version 3, and to the CodeIgniter community for their support and contributions!
Edit: Fixed the links

Changes compared to CodeIgniter 2:
- The framework is released under the MIT license
- The database drivers have had extensive refactoring
- PDO is fully functional with subdrivers
- There is a new Session library
- There is a new Encryption library
- The unit testing has been beefed up, and code coverage improved
- PHP 5.4 or newer is recommended, but CI will still work on PHP 5.2.4
Here are some instructions for upgrading to CodeIgniter 3 from CodeIgniter 2.
Many, many thanks to @narf for shepherding version 3, and to the CodeIgniter community for their support and contributions!
Edit: Fixed the links

James Parry
Project Lead
Project Lead