• by Shankar Gupta , April 27, 2006

The Google main search page, long off-limits for display ads, Wednesday hosted an ad for the Firefox browser, marking the first time ever that the search giant has promoted a non-Google product or service on its home page.

The development is significant because marketers have clamored to show ads on the Google home page for years, said Gary Stein, a search expert and former analyst with Jupiter Research. "Any media agency worth their salt is on the phone saying, 'Hey, sign us up,'" Stein said. "It's been the most sought-after piece of real estate for five years now, and it's been totally off-limits, and I don't think you just let this go by."

The ad appeared on Tuesday, and was taken down Wednesday afternoon. It was only displayed to people using the Internet Explorer browser and its call to action--download Firefox--can easily be seen as a direct shot at competitor Microsoft. "It's not like you needed too many more signals that they were going to aggressively position themselves against Microsoft," Stein said.

Industry-watcher John Battelle mused on his blog that "Up at Microsoft, they're probably ordering new chairs for Ballmer's office," referring to a report that Microsoft CEO Steve Ballmer hurled a chair across the room and when he was informed that former Microsoft engineer Kai-Fu Lee would be heading to the Mountain View search giant.

In January, the search giant began backing Firefox, an upstart competitor to Internet Explorer, with the introduction of the Google Pack, a software package that included a host of Google and non-Google applications, many of which--including Firefox, RealPlayer, and the Trillian cross-platform instant messaging client--compete directly with Microsoft software. The move was viewed at the time as a preemptive strike against the possibility that Microsoft will incorporate a toolbar in its next version of Internet Explorer, making it easier for users to go to MSN than Google.

Google did not return calls for comment for this article.