Firefox 4 slips out before official launch

Mozilla has quietly released Firefox 4 in advance of an official announcement.

The popular browser's fourth incarnation is available for download now in Linux, Mac OSX and Windows versions, a few weeks late for its planned February launch.

The downloads, which range from around 12MB for Linux and Windows up to a suspiciously bloated 26MB for the Mac version are well hidden within the Mozilla Foundation's web site with the main download page still defaulting to version 3.6.

We've been fiddling with the latest iteration for just a few minutes on our Mac Pro and everything seems pretty stable so far.

There have been some minor tweaks to the GUI with Chrome-like tabs now appearing above the main browser bar, but it's the refinements under the hood which should see web wanderers flocking to Mozilla's open source offering.

Improved HTML5 and CSS support should make those complex pages look even prettier and the addition of WebM support will allow HD video to be viewed in a browser window.

WebSocket support will allow developers to build online games and applications whilst indexed DM allows web apps to store data on your home system allowing products like Gmail to work even if you don't have an Internet connection.

Firefox is a firm favourite here at thinq_ being the browser of choice for use with the CMS system used by our crack international team of tech hacks, so we'll be watching the progress of Firefox 4 closely, and will bring you a full review once we've had some tinkering time.