Firefox → Yahoo

This is a mistake. Firefox is already losing mindshare in Silicon Valley, partly because there seems to be a widespread perception that Chrome is just faster than Firefox, but the power-user features of Firefox don’t seem to have enough appeal. Firefox switching to Yahoo for search will cement the impression that Firefox is to browsers what Yahoo is to search, that is, a distance second (third?) place. In practice, Firefox is a superb browser for lots of reasons, but its victory is far from guaranteed.