Nielsen released its version of the U.S. search market rankings for July today. Google is of course on top with 3 out of 5 searches (64.2%). Yahoo came in second with 14.3%, leaving Microsoft in third at 13.6%. Yahoo and Microsoft both gained in month-over-month share (2% and 4%, respectively). This is all good for Microsoft, as Bing has now completely overtaken Yahoo's organic results in the U.S. and Canada. We'll see our first glimpse of how this is working out next month.