Here's an article from David Passell which compares worldwide use of Mac vs PC. He notes, "Also compares different browsers." http://www.zdnet.com/article/which-operating-systems-and-browsers-are-most-popular-in-the-u-s/?tag=nl.e539&s_cid=e539&ttag=e539&ftag=TRE17cfd61
Two shakes later Jim Hamm sends this same link, heading it with "Six surprising facts abut who's winning the operating system and browser wars in the U.S." His comment is, "Not that it will change what you use, but here are some interesting statistics . . . "