According to the monthly Media Metrix report from Internet market research firm comScore, Google in May became the first web property to pass one billion unique visitors worldwide.

Even as the most popular web property in the world, Google still managed to grow its audience by 8% between May 2010 and May 2011. According to comScore, this increase was common among all of the top web destinations, with Microsoft, Facebook, Yahoo, and Wikimedia sites all trending upward over the year.

Facebook, the third most popular web property with 713.6 million uniques grew between April and May 2011, but data from Inside Facebook suggest the popular social networking site's growth may begin slowing globally.

Google shows no signs of stopping.