Opera Software is changing its tune, in regard to search engines. No longer will Yahoo be the default search engine for its popular Opera Mini and Opera mobile Web browsers. Instead, just like with the iPhone, Google will now be the company's browser of choice as it has been on the desktop for the last seven years. As a result, Google will become accessible directly from both the Opera browsers' start pages.

"Google and Opera have established a valuable relationship over the years and we look forward to continued collaboration on mobile products," explained Opera CEO Jon von Tetzchner. "With 2008 poised to be the year the mobile Web goes mainstream, Google and Opera are extending this collaboration to give our users immediate access to the quality and convenience of Google's search results."

With the mobile wars heating up, Google's win is no small thing. By becoming Opera's go-to search engine, it gains direct access to tens of millions of additional hands and, even more importantly, eyes. Opera Mini has - for example - been installed on over 100 million phones and used to browse over 1.7 billion pages.

Not only that, since most people don't bother changing the default search engine on a mobile browser, even if they prefer another one, today’s news gives Google a huge advantage over competitors like Yahoo in the mobile space.

Opera Mobile is available for Windows Mobile and the Symbian platforms. The latest version, the recently introduced 9.5, is supposed to offer a number of improvements. So there's now iPhone-like zooming and panning in addition to productivity tools like the ability to save pages for offline browsing, Web address auto complete, and a password manager, for example.

Also, its rendering engine, called Presto, has been modified to accelerate the handling of Web pages that rely heavily on languages like JavaScript and Ajax. This should also make Opera Mobile more responsive when loading sites.

Opera Mini is the Norwegian company's free mobile browser for Java-capable mobile phones and smartphones.