I remember switching a lot of non-techie friends/family to Firefox but I see them using Chrome now. When I ask about Firefox the answer almost invariably is that they didn't know how Chrome got on their PC.
Site owners get as much as $1 per Chrome download that they're able to push their visitors to. I don't think Firefox has these kinds of resources against Google trying to minimize how much they pay Firefox by cutting down the middle man and building a moat around their search engine and ad profits. The next good search engine to come by will certainly not be the default on a large percentage of browsers.