Canonical, the company behind the popular Ubuntu Linux distribution, revealed today that it has established a revenue sharing agreement with Yahoo. As part of the deal, the Firefox Web browser that is shipped in Ubuntu will be configured to use Yahoo as the default search engine.

Rick Spencer, the leader of Canonical's desktop team, announced the search engine change today on a public Ubuntu mailing list. The specific terms of the agreement have not been disclosed. According to Spencer, the new default will appear in the development version of the distribution "as soon as reasonably possible" and will be in place in time for Ubuntu 10.04, which is scheduled for release in April. They have not indicated whether the change will be applied retroactively to existing installations of the current stable version, but they have confirmed that it will be changed for existing users who upgrade from the current stable version to 10.04.

The change will encompass both the search provider in Firefox's toolbar and the default start page. Users will still be able to quickly change the default search service by clicking the search provider icon in Firefox and selecting the search service of their choice from the dropdown menu. In order to make it easier for users to switch completely, Canonical is customizing the browser so that switching your default search provider will also change your start page if you haven't already set one.

Canonical is unusual among major commercial Linux distributors in the sense that it doesn't sell an "enterprise" or "pro" version of its software. In an effort to make this approach sustainable, Canonical is experimenting with a number of different business models, including commercial support for end users, subscription-based Web services, and integration support for hardware makers. In the announcement about the search engine change, Spencer says that Canonical's partnership with Yahoo will help to fund the ongoing development of the distribution.

"I am pursuing this change because Canonical has negotiated a revenue sharing deal with Yahoo! and this revenue will help Canonical to provide developers and resources to continue the open development of Ubuntu and the Ubuntu Platform," he wrote. "This change will help provide these resources as well as continuing to respect our users' default search across Firefox."

Canonical currently gains a portion of the revenue from Google searches, so the change means that Yahoo offered a better deal. Search partnerships have become increasingly common. The development of Firefox itself is largely funded by Mozilla's relationship with Google and other search providers. Hardware vendor Dell already ships Yahoo as the default search engine in its Ubuntu-based systems due to its own revenue sharing deal with the search company.

It's worth noting that Yahoo's data retention practices are more privacy-friendly than Google's. Yahoo search records are anonymized after 90 days, a practice that will continue in the future. Google, on the other hand, keeps the data for three times as long and has faced criticism for its allegedly inadequate anonymization.

The move has generated a bit of controversy among some Ubuntu enthusiasts who are concerned by the adoption of a default that doesn't represent the general preference of a majority of the users. In practice, the ease with which the default can be changed largely mitigates any potentially detrimental implications. As long as Canonical's efforts to monetize the desktop doesn't escalate into the kind of crapware epidemic that has infected the major PC makers, it's not going to be a problem. Selling the default search seems like a fairly uninvasive and practical way for Canonical to boost its revenue, thus helping to ensure that the company can continue to provide its software to users at no cost.