Mozilla sets Firefox 3.5 final release for Tuesday

Mozilla will ship Firefox 3.5 on Tuesday, bringing the long-awaited upgrade in under its own deadline wire, the company announced last Friday.

According to a Mozilla spokeswoman, the final version of Firefox 3.5 will be posted for download today.

The news was not a surprise. Last Thursday, Mike Beltzner, the director of Firefox strongly hinted that Firefox 3.5 would meet the ship deadline of the first half of the year. “Everyone's pretty happy with the release, and while we haven't picked a date yet, we're still tracking to our latest schedule,” Beltzner said in an e-mail.

Mozilla made its deadline by running an unusual, accelerated set of release candidates (RC) that were issued primarily to the 800,000 users running earlier previews of the new browser. In early June, it pushed an interim “Preview” build it described as a nearly-finished RC and last week it wrapped up the process with several quick RCs.

The release comes just over a year after Firefox 3.0 debuted.

Firefox 3.5 was originally slated to be called Firefox 3.1, but the company decided in March that it had added enough new features to justify the larger bump in number from last summer's Firefox 3.0.

Among the features to debut in Firefox 3.5 are a new, faster JavaScript engine called TraceMonkey; a privacy mode, which some call “porn mode” for one of its more obvious applications; and location-aware browsing. Mozilla has also touted numerous under-the-hood performance improvements, ranging from support for new video and audio HTML5 tags to support for Web worker threads — enhanced scripting that lets site developers shift JavaScript computations to a background thread.

At one point, Mozilla was shooting for a quick turnaround for Firefox's next upgrade, saying last year that it hoped to wrap up work before the end of 2008. Those plans were made moot, however, by Mozilla decisions to delay the upgrade in order to add TraceMonkey and the new privacy mode, among other things.

In January 2009, Mozilla pushed back the release of Beta 3 multiple times, citing hard-to-patch bugs as the cause of the delays.

Firefox accounted for 22.5% of the browser market, according to the most recent data from Web metrics company Net Applications. It faces renewed competition on almost every front, including Microsoft's Internet Explorer 8, Google's Chrome, Opera Software's Opera and Apple's Safari 4.

When Mozilla releases Firefox 3.5 for Windows, Mac and Linux, it will be available for download from the company's site. Existing users will be able to grab it by selecting “Check for Updates” within the browser.

If users rush to download Firefox 3.5 as they did with version 3.0 last summer, users may experience delays getting the upgrade. In June 2008, Mozilla's download servers went down under the load for about an hour before the company was able to restore service.