The latest development milestone release (Herd 4) for the Ubuntu project’s next release, Feisty Fawn, has been released. This release will become Ubuntu 7.04 on April 19th 2007.
Pre-releases of Feisty are not encouraged for anyone needing a stable system, or anyone who is not comfortable running into occasional, even frequent breakage. They are however recommended for Ubuntu developers and members of the community who want to help in testing, reporting, and fixing bugs.
The primary focus during the time betweeen Herd 3 and Herd 4 has been a mix of feature development and bug fixing. More details about recent changes can found on the Ubuntu and Kubuntu Herd 4 pages.
You can read the complete release announcement which also contains links to the mirrors where you can get Herd 4.