Honestly I dont see how this is a "choice". In fact this sounds exactly opposite of the choice. In this particular case Firefox has made the choice on our behalf that we are better off using Yahoo's crappy search results instead of market leader Google. If you are making a browser which is focused on giving freedom to users you are supposed to : 1. Either let the users chose the search engine as an on-boarding step.…
Part of the deal is that Yahoo improves the presentation of search results so that this doesn't happen.