Firefox 3.0 represents nothing more than the end of a development cycle that will produce the successor of Firefox 2.0. But even if Firefox 3.0 is yet to be finalized, available now as RC3, and the release date is set for June 17, Mozilla is already hard at work on the next generation of its open source browser. Firefox 3.1 codenamed Shiretoko could end up as version 3.2 or even 3.5, but the fact of the matter is that nothing is set in stone yet. Not even the delivery date for the first Alpha build, which is planned for mid-July 2008.

Mike Beltzner, Mozilla’s User Experience Lead revealed that "very early draft of the Firefox 3.1 plan available at the Firefox 3.1 Planning Center". Firefox 3.1 Shiretoko will be based on Gecko 1.9.1 and will be designed to bring to the table some of the features and functionality that were cut from Firefox 3.0.

As early as Alpha 1, Mozilla plans to add a collection of features including the ability to "show page preview when using Ctrl+Tab, all tabs preview/find pane, lightweight tagging UI, Tag Autocomplete, Advanced Search UI, Bulk tagging support, Download History integration, Enhanced compatibility checking during upgrades and coherent startup/shutdown prefs/behaviours".

In this context, Firefox 3.1 will be nothing more than a minor update to version 3.0. Mozilla already announced that it planned to ship Shiretoko by the end of 2008. Beltzner indicated that Firefox 3.1 codenamed Shiretoko was planned to be feature complete in no less than six weeks.

"Alpha release criteria: Alphas must be generally usable for testing websites and features, no significant features broken, major/high value sites should function and display in a reasonable fashion. Beta release criteria: Betas must be stable and usable enough for daily browsing for a large number of people, features are fully implemented, if not finalized, most sites should display properly and regression free (from previous major release)", Mozilla informed.

Firefox 3.0 RC3 is available for download here.