If you're a Firefox user, you may have recently been notified of an update to the software letting you know that it is now recommended to upgrade to the latest stable version of Firefox 5. Did you blink twice? Indeed soon after the release of another major version, the final release of version 5 is here. Many are now asking why their favourite Internet browser has jumped from 3.6.8 to 4.0/4.01 and now to 5.0 after being used to the version 3.x branch for so many years. Only very recently did Mozilla move Firefox 4 out of beta.

It's strange that users of Firefox are now being asked to upgrade to the 5.0 stable release so soon after they switched to the 4.x stable branch. So why is Firefox 5 out so soon after Firefox 4? The official answer is that Mozilla is moving Firefox to a rapid release schedule.

By the look of things, Firefox 5.0 actually resembles version 4 in many ways. It looks the same, it feels the same and cosmetically, it really doesn't offer much more than recent previous versions. Even then, the 4.x branch was mostly a polished up version of 3.6.8 but with the highly anticipated arrival of better standard conformity and especially full CSS 3.0 and HTML5 implementation. Worth noting is the layout engine behind Firefox 4 and 5 has been upgraded to Gecko 2.0, while Firefox 3.5+ used the Gecko 1.9.1 engine.

Without the huge fanfare with the release of Firefox 5.0 like we saw with 4, we're a little bit curious whether there was some serious security issues under the hood of Mozilla's popular browser or whether it's simply because of the growing popularity of Google's Chrome browser. Mozilla may even be taking a nod from Google's strange version numbering which seems to have gone from version 0.2x to 11.0 in a matter of a 3 years.

There's been a storm brewing in the Internet browser market for the past year with Google gaining a very large market-share and Microsoft Internet Explorer losing some. Before Chrome became heavily marketed by Google, Firefox was subsidized by Google to the tune of tens of millions of dollars per year. Google pledged back in 2008 to continue its support of Firefox development until at least 2011 while Google Search remained the default search engine on standard installations.

Though pure speculation, the big financial support of Firefox by fellow Mountain View company Google seems to be coming to an end, at least one would think. With Chrome's worldwide browser share at around 17% creeping up to Firefox's 27%, the next-generation browser wars have already started. One point worth noting is Google's toolbar is not yet available for Mozilla's newest release, a tool Google has admitted collects anonymous user browsing habits.

Another point about this release which may also affect a Firefox-Google relationship is the better privacy features of Firefox 5 which sports an improved and fuller implementation of the Do-Not-Track header, something Internet Explorer, Firefox, Safari and Opera all signed onto while Google refused calling the technology “useless”.

On the other hand, the above is all pure speculation. Firefox has apparently changed over to a rapid-release schedule meaning they plan to release new versions of the browser every 1 ½ months, meaning a Firefox 6 could be released as early as August.

If this update is news to you and you'd like to give Firefox 5 a whirl, you can download Firefox 5 here or open up the about box (in Firefox, hit tab, select “Help” → “About”) and Firefox should notify you of a recommended update. The move towards a more private browsing experience, albeit slow, is rather refreshing.