Is this a big deal? Not really. It is easy enough to change the search settings on Firefox. Just click on the tab just to the left of the search bar and select which engine you wish to use. It is the little search engine icon. Then the default is set. Even if you quit and restart your browser.
The funny thing is that Yahoo is actually paying Cannonical to have their engine set as a default. Since Microsoft is now in partnership with Yahoo, in a sort of weird way, Microsoft is paying a share to build and distribute Ubuntu. Still, not quite as overt as the Novell deal, but the link is there.
Will there be a backlash against Ubuntu in the Linux world? Who knows. Let the griping begin!
I have been using Chrome a lot anyways. It seems to work quite well.