Mozilla's Firefox 4 handily beat Microsoft's Internet Explorer 9 in the number of downloads during the first 24 hours the final versions of the browsers were available.

Mozilla reports that the latest version of its open-source browser was downloaded 7.1 million times, giving the company bragging rights over Microsoft. The latter reported last week that IE 9 was downloaded 2.35 million times.

Mozilla's achievement doesn't go much further than a pat on the back, since the total number of IE 9 downloads will quickly surpass Firefox once Microsoft distributes the browser to the millions of Windows Vista and Windows 7 users as a free software update.

The Firefox 4 downloads does show that the browser remains popular with current users, while not the must-have of Firefox 3. That latter had 8 million downloads in 24 hours in 2008.

The release candidate of Firefox 4, which became the final version of the browser, was downloaded more than 3 million times, so the total number of Firefox 4s installed on Macs, Windows and Linux PCs was more than 10 million, according to Mozilla. The final Firefox version was released March 22.

In a couple of weeks, Mozilla plans to release a version of Firefox 4 for mobile devices running Android and Maemo operating systems. Users can sync their Firefox bookmarks, passwords, preferences, history, and tabs between multiple computers and mobile devices.

IE's dominance of the browser has slipped over the years, falling to roughly 56% in February from about 70% two years ago. Firefox has about 21% of the market, followed by Google Chrome with 11%, and Apple Safari with 6%, according to Web metrics firm Net Applications. Chrome use is the fastest growing, rising from a 7% share in April 2010.

The importance of the browser on personal computers accessing the Web is diminishing steadily, as people turn to smartphones, tablets, and other Web-enabled mobile devices. Because those devices also have browsers, the technology is expected to remain an important Internet gateway for some time to come. How much influence a browser maker has in the future of online computing will depend on market share, analysts say.

In the future, even the browser's importance is likely to diminish, as people increasingly access Web services directly from mini-apps running on their devices. That trend is expected to take years, keeping browser use strong for quite awhile.

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