How did Yahoo beat Google in Website rankings in July

Hey, we aren't the only ones who are surprisde. But, according to the comScore Media Metrix service, Yahoo had 3 million more unique visitors in July than Google.  Apparently this vindicates Marissa Mayer, former Googler and presently CEO of Yahoo. And, frankly, it is mystifying. I mean, for the all the crap Yahoo has gotten these last few years and the notion that Mayer was a little bit of a dilettente, you can't argue with the numbers.