Washington Post – There’s some good news for Yahoo chief executive Marissa Mayer: Yahoo topped Google in Web traffic for the first time since May 2011. Research firm comScore reported Yahoo logged 196.6 million unique visitors in July, compared with its rival’s 192.3 million. The bump in traffic should be encouraging news for Mayer, a Google alum who has focused on overhauling Yahoo’s image in the year since she took the helm at the technology giant. When Mayer started at Yahoo last July, the company trailed Google by 5 million page views — with 163 million unique visitors to Google’s…