Firefox 3.5 is only 3 months old, but it appears that the folks at Mozilla may be ready to replace it. The reasoning is that the newest version is based on a new Gecko engine that may improve performance. If you would like to try the beta [test] version you will be able to download it immediately from the Mozilla site linked below.
According to a recent article over at Softpedia it also states that:
Chris Ilias posted an interesting question to Mozilla: “As I understand it, Firefox 3.6 will be treated as a minor update to 3.5.x. Does that mean that there will not be any 3.5.x updates after 3.6 is released?” The answer he received came from Mike Beltzner, director of Firefox at Mozilla Corporation.
“It’s not 100% decided yet, but if we issue a Firefox 3.6 as a minor update, then yes, we’d stop supporting the 1.9.1 branch at that time. There are several confounding issues with this approach, however, the most notable being that Seamonkey and Thunderbird will be based on mozilla-1.9.1,” Beltzner stated.
1.9.1 is a reference to Gecko 1.9.1, the underlining rendering platform of Firefox. While Firefox 3.5 is based on Gecko 1.9.1, Firefox 3.6 is based on Gecko 1.9.2, the next iteration of the open-source rendering engine.
The inherent downside of a fast-paced development process is the fact that the version number of Firefox will change twice this year, generating modifications throughout the ecosystems of add-ons for the browser in order to deliver compatibility. The end of support for Firefox 3.5 will force users to upgrade to version 3.6, or keep running a browser that will no longer receive security and stability updates.
Firefox 3.6 is currently planned for general availability in November 2009, and users should get ready for a similar minor update experience in the first half of 2010. Firefox 3.6 will be succeeded in just a few months by Firefox 3.7. And Firefox 3.7 itself will be replaced by Firefox 4.0 in October 2010 at the earliest.
But Mozilla traditionally keeps major versions of its open-source browser alive for a maximum of six months after a new major version of Firefox is released. It is the case of Firefox 3.0.x, which will no longer be supported as of January 2010, six month after Firefox 3.5 was released.
If you are currently using Firefox, may I recommend you get yourself the add-on FEBE. FEBE backs up your Firefox profile just in case something goes wrong when you upgrade to a newer version.
The latest releases of Firefox for Windows are available for download here.