Mozilla plans to sell sponsored content, just a fancy word for advertising, in its new Tab pages. The New Tab pages will have some Mozilla-specific content, some popular websites, as well as some hand-picked sponsored content. Mozilla receives about $300 million per year from Google for making Google the default search engine for its Firefox browser. The deal is due up in December. Could it be that Mozilla is just trying to diversify its income stream just in case Google changes its mind.