For those of you who enjoy staying on the cutting edge, Mozilla has released the first alpha of Firefox 3.1. This latest version, code-named Shiretoko, is built on top of Mozilla's Gecko 1.9.1 rendering engine which is also in development and promises better support of web standards.

New features in this release include filmstrip-like visual tabbed browsing using the Ctrl-Tab shortcut, the ability to restrict results that appear in the Smart Location Bar, and a few aesthetic touches. Firefox 3.1 alpha 1 has a few treats for web developers too, including some long-awaited CSS3 features like border images, and support for JavaScript query selectors.

Shiretoko is aimed at developers and testers who want to participate in the development by helping to spot bugs, though anyone can give it a try – it won’t overwrite your existing Firefox 3.0 install.