Roughly speaking, search engines pay browser vendors (including even Apple) for traffic. See for instance some analyst's speculation about a Google-Apple deal

Roughly speaking, search engines pay browser vendors (including even Apple) for traffic. See for instance some analyst's speculation about a Google-Apple deal here: http://news.ycombinator.com/item?id=5206764 http://news.ycombinator.com/item?id=5206764