First look: Firefox 3.1 beta 1 officially released

Mozilla has announced the availability of the first Firefox 3.1 beta release, an important development milestone for the popular open source web browser. Mozilla aims to make Firefox 3.1 a strong incremental improvement with user interface enhancements, new features, and increased support for emerging web standards. The new beta release includes a modest handful of noteworthy changes that improve the user experience.

Mozilla had originally planned to start code freeze for beta 1 in the middle of August, but decided to delay the beta release and do an additional alpha release instead.

The beta includes Mozilla's new TraceMonkey JavaScript engine, which uses tracing optimization to deliver a massive performance boost that makes it faster than Google Chrome's V8 engine. Although it still falls short of Apple's recent Squirrelfish Extreme project, the Mozilla developers say that TraceMonkey still leaves plenty of room for additional optimization

Although TraceMonkey is finally included in beta 1, the new engine isn't actually enabled by default. It is still under heavy development and it reportedly exhibits some bugs that could impact JavaScript reliability. To configure TraceMonkey in beta 1, browse to "about:config" and then toggle the "javascript.options.jit.content" variable.

Another major feature that is included in this release is Mozilla's new implementation of the W3C Geolocation Specification. It allows web applications to obtain information about the user's geographical location through a simple JavaScript API. In beta 1, this functionality is built on top of the Loki web service, which is supplied by Skyhook and determines the user's position by comparing local WiFi access points with information in its global reference database. For privacy reasons, the browser will automatically prompt the user before supplying a web site with geolocation data.

Several web sites already have basic support for the feature, including Yahoo's Fire Eagle and the Pownce microblogging service. We tested it with Outside.in Radar, a new web service that displays news headlines and other information about things that are near the user's current location. Earlier this month, Mozilla Labs also released the Geolocation Specification implementation as a Firefox 3.0 extension called Geode so that users and developers can start testing the functionality and incorporating support for the APIs into their web applications without having to use Firefox 3.1 prerelease versions.

In addition to these new features, beta 1 also includes a lot of other improvements that we have looked at in previous alpha and nightly builds. Firefox 3.1 alpha 1, which was released in July, introduced new tab switching behavior and a new visual tab switcher with graphical thumbnails. The alpha 2 release, which was made available earlier this month, added support for the HTML 5 video element which makes it possible for the browser to natively display playable video and seamlessly intersperse it with HTML and SVG content.

Mozilla is actively working on many other features that are planned for Firefox 3.1, but haven't been fully implemented in this beta release. Future versions will include a new private browsing mode that is similar to the one in Google Chrome. Mozilla is working on some nice user interface improvements too, such as support for tag autocompletion in the bookmarking interface.

Firefox 3.1 is evolving swiftly and each new prerelease delivers impressive changes. Users can look forward to a great 3.1 release with lots of good improvements and great support for open web standards. The new beta release is available for download from Mozilla's web site and additional information can be found in the official release notes.