ComScore -- a common metric used to measure internet traffic -- is showing off some impressive stats these days. In the month of November, for instance, Facebook overtook Yahoo! for the first time in worldwide traffic, with the social network nabbing 648 million unique visitors while the portal named after Gulliver's Travels pulled in 630 million. What does this mean to? Well, to point out the obvious, it seems that while Facebook continues its epic growth, the relatively flat state of Yahoo!'s traffic is simply not enough to retain its third place spot behind Google and Microsoft's sites, which grab up places one and two consistently. One note about these ComScore statistics, just in case you're wondering about that last one: it 'groups' sites together rather than counting individual URLS, so for instance, the Microsoft sites take the number two spot en masse. In terms of U.S. traffic, Facebook still trails Yahoo! a bit, with 152 million visitors and 181 million, respectively, so if they're truly hoping for world domination, they have their work cut out for them. We're looking at you, Mark!