Is the search-engine market ready for a little dash of creative destruction? We’ve grown accustomed to a landscape dominated by the formidable Google mountain, their company name becoming the preferred euphemism for the very act of using a search engine. However, as Bloomberg News reports, Google just experienced its biggest loss of market share since 2009, to the benefit of Yahoo, which is hungry for good news right now:

Google’s slice of the U.S. search market fell to 75.2 percent in December from 79.3 percent a year ago, while Yahoo jumped to 10.4 percent from 7.4 percent, according to analytics firm StatCounter. That put Google at its smallest share of the U.S. Web search market since at least 2008, when StatCounter first started tracking the numbers, and the highest share for Yahoo since 2009.

The changes were spurred by a deal in November where Yahoo replaced Google as the default search engine on Firefox browsers in the U.S. Google had been the automatic search option for Firefox, which was developed by Mountain View, California-based Mozilla Corp., since 2004.

“The move by Mozilla has had a definite impact on U.S. search,” StatCounter Chief Executive Officer Aodhan Cullen said. “The question now is whether Firefox users switch back to Google.”

Firefox users represented slightly more than 12 percent of U.S. Internet usage in December, according to StatCounter.

This is an interesting demonstration of how powerful corporate synergy can be. It’s very easy to change the default search engine in any browser, including both Firefox and the one Google created, Chrome. Chrome is famed for pioneering the concept of an “omnibox,” a single unified window at the top of the browser that will accept either a web address or search terms.  If you type in a web address, the browser goes to that site.  If you type in anything other than a web address, a search is automatically performed.  Similar functionality now exists in nearly all browsers, although most of them also have separate, redundant boxes in their interface clearly labeled “Search.”

In every case, the browser ships with a particular search engine selected by default – not surprisingly, it’s Google for Chrome, and up until now it was also Google for Firefox. Changing the default browser requires only a few mouse clicks; both Firefox and Chrome allow users to change their search engine choices by simply-right clicking in the search area and selecting a very obvious option for editing or managing search preferences. And yet, a large number of users are evidently willing to stick with whatever the default option is. When Firefox, which is only the fourth most popular browser, switched its default search engine to Yahoo, the result contributed to a very noticeable crack in the Google monolith, plunging the search giant to its smallest market share in six years, while boosting Yahoo to a six-year high. That will be very welcome news for Yahoo’s advertising partners, who will be pleased with the thought of so many more routine searches summoning a Yahoo results page.

Interesting side note: Firefox is the number-four browser, but the current Number One is no longer Microsoft Internet Explorer – it’s Google Chrome. After years of market dominance, Internet Explorer slipped under Chrome this year, and it’s widely credited to another bit of marketing synergy. Chrome is part of a package of applications that includes Google’s popular Gmail suite, and they’re all frequently delivered as default applications on Android smartphones and tablets, while Internet Explorer has no mobile presence. Microsoft’s product, for its part, became King of All Browsers by shipping for free as part of the Microsoft Windows operating system that most personal computer users rely upon, a bit of aggressive synergy that became the subject of headline-grabbing lawsuits back in the Nineties.

The Number Three browser is currently Apple’s Safari, which had a brief run on the Windows platform, but is mostly known as the default browser for Apple computers these days.  That might lead to some more bad news for Google, as Business Insider reports:

There are reports that Apple is considering dropping Google as its default search engine on the iPhone’s Safari web browser. It’s not clear what Apple might replace the search giant with, but whether Yahoo, Bing, or an in-house search, it would be a big loss for Google. The Journal reports that in December, more than half of all US mobile traffic came from Safari.

There’s a precedent for this: Back in 2012, Apple replaced Google Maps with its in-house Apple Maps app. The software was terribly received and plagued with bugs — but Apple seems to have learned from its mistakes. The map data has been gradually improving, and Apple CEO Tim Cook eventually released an apology over the new app.

Cook was so angry over the Google Maps controversy that he reportedly fired a top Apple executive. If Apple is planning on ditching Google again, it’s going to ensure the alternative it comes up with is up to the task.

That would be a much bigger hit against Google than losing Firefox, while landing a plum spot as the default browser for Safari would be a dream come true for Yahoo. Yahoo CEO Marissa Mayer is lobbying Apple hard for that position, while Microsoft is making the same pitch for its Bing search engine. There’s one big hurdle for Yahoo to overcome: Bing is already the default search engine for Siri, the famed voice-response system on iPhones. It would seem only natural for Apple to make Bing the default for the Safari browser as well, once their deal with Google runs out.

However these deals shake out, there’s not much apparent danger of Google being dethroned as the top search engine any time soon.  However, some analysts have warned that Google has peaked, or rather is approaching its peak – it’s still growing at the moment, but the rate of growth has begun to slow.  The bulk of its income comes from advertising revenues generated by its search engine, and if competitors are able to erode its dominance – including foreign competition that has already taken a strong position in global search traffic, and made progress on technological innovations where Google’s research appears to have stalled – there really might be nowhere to go but down.

It’s interesting that there’s so much non-Google market space left for others to fight over, and it’s fascinating that so much of the battle is decided by the simple convenience of bundled applications and default preferences. This is no doubt a result of the similarities between products, and the high degree of competence all the major browser and search options bring to tasks demanded by average users; for the moment, at least, we seem to be past the days when user stampedes to new platforms would be triggered by intense dissatisfaction. With a vast buffet of choices spread conveniently before them, a hefty slice of the user base for all manner of cutting-edge computer systems is content to use whatever manufacturers put on their plates.