Mozilla will officially launch its Firefox 4 web browser today, about eight months after its first public beta. But many of the features in Firefox 4 really date back to 2006, and the lengthy time to market for this release—during which Firefox usage essentially stopped growing in the face of faster-moving rivals—has caused the firm to step back and reevaluate its product plans. And the goal going forward is to ship smaller releases on a far timelier schedule.

The question, of course, is whether it's already too late. Google has shipped an astonishing 10 major releases of its Chrome browser since its initial release over two years ago, and that company says it is able to maintain this pace by thinking of Chrome as a web service instead of a traditional software product. Even Microsoft, not known for moving quickly, has made Mozilla look sleepy by comparison: It shipped the final version of its new browser, Internet Explorer (IE) 9, last week after just 6 months in beta.

Mozilla has historically had trouble meeting release dates, and Firefox 4 required an astonishing 12 beta releases and 2 release-candidate builds before the company was able to sign off on the product. For the new schedule to work, Mozilla doesn't just need to deliver smaller, more conservative updates; it needs to do something it has never done: Ship them on time.

"The intention here is not to rush features, it's to let features that are done get to users without waiting for features that aren't." Mozilla VP Mike Shaver explained. With Firefox 4, certain browser features were ready to ship months earlier, but because they relied on other pieces of that browser version, Mozilla had to wait before shipping them.

As for Firefox 4, Mozilla's new browser hopes to differentiate itself in important ways. It runs on Windows XP, for example, whereas IE 9 supports Windows Vista and Windows 7 only. Firefox 4 has a nice new user interface; an overhauled, faster JavaScript engine; bookmark syncing; and more.

It's not all peaches and cream. Firefox 4 supports only partial hardware acceleration—a far cry from the performance that users will see in IE 9. And it trails both IE 9 and Chrome, overall, from a performance standpoint. Some don't like its old-school separation of address bar and search bar into two separate UI elements; most other browsers have integrated these into a single control.

As of this writing, Mozilla hasn't yet updated its site to promote the new release. But you can download the final Windows version of Firefox 4 by clicking here.