Mozilla, the makers of Firefox internet browser (the only notable competitor to Microsoft’s Internet Explorer), has extended its deal with Google – meaning the search giant will continue to be the default search engine on all its Firefox installs until 2011.

The deal, which was first agreed on in 2006, represents the single biggest income stream for Mozilla, almost 85% of its total income (approx $57M in 2006).

Users of the Firefox browser are able to change their preferred search engine once it’s installed, however complacency by users often sees the default remain in place permanently.

Last year, Mozilla’s former CEO was adamant that the company would walk away from the lucrative deal, should it compromise the independence of the company – not wanting to become just another arm of the Google empire. Hard to believe when you’re talking about almost all your organization’s revenue.

Either way, it appears that Mozilla’s independence remains intact and Google yet again gets one up on its primary competitors Yahoo! and Microsoft.

Being the search engine default on browsers isn’t the “be all and end all” of market dominance. Google still reigns supreme even though Microsoft’s Internet Explorer holds over 70% of the browser market.

Though Microsoft dominates the browser world, Mozilla continues to gain ground, with recent estimates suggesting its share is closing in on 20%. When you consider how many internet users there are in the world – Google’s deal will ensure its the first search engine many millions of new Firefox users see.

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