Gran Paradiso Alpha 4 is now available for testing. New features in this development milestone of Mozilla Firefox 3 include the FUEL JavaScript library for extension developers, a redesigned Page Info window, improvements to offline application support and Gecko 1.9 bug fixes.
Several Mac OS X additions have also been made, including support for Growl notifications, improvements to the Cocoa user interface and an initial version of the Breakpad crash reporting tool.
Gran Paradiso Alpha 4 is intended for Web developers and the Mozilla testing community only, with regular end users strongly advised to stick with the stable Firefox 2 for now. Alpha releases of Firefox 3 are branded using the Gran Paradiso codename in an effort to discourage regular end users from downloading them.
Read more at mozillaZine.org