With the partnership between Mozilla and Google running out at the end of the month, it looks like the relationship between the companies will now be significantly smaller as the former will adopt Yahoo Search as its default search engine starting in December.
The blog post by Mozilla CEO Chris Beard makes it sound like the company wanted to do something new and innovative because being an independent organization, Mozilla can choose to do whatever it wants. It is worth noting that the Google partnership goes back to 2004 so this change probably did not come lightly. Furthermore, Firefox will continue to support Google but users will simply have to change their default option from the respective menu in order to get it.
Interestingly enough, Yahoo will not start supporting Do Not Track (DNT) requests in Firefox. The company had previously announced that it would stop honoring DNT requests but it seems like that was unacceptable to Mozilla and a compromise was made. To be blunt, I think the update is good for both companies. Users that actually care about the search engine should find it very easy to change their default search engine while those who do not will probably not notice that the search engine has been changed.