Google remains the world's largest Web property with about 970 million unique visitors in November 2010, followed by Microsoft with 869 million and now Facebook. In comScore's October rankings, Yahoo and Facebook were virtually tied with 633 million worldwide visitors each. Facebook had been gaining on Yahoo throughout the entire year, so it is more or less appropriate that the rapidly growing social networking site take hold of the No. 3 spot as we move into 2011.
Facebook held the fourth position for nearly a year and a half after passing the Wikimedia Foundation sites that include Wikipedia back in August 2009. Other notable sites it has passed along the way during its meteoric global rise include MySpace in April 2008, Amazon in August 2008, eBay in January 2009, AOL in February 2009, and now Yahoo.
Facebook also accounts for almost one quarter of all display ads in the United States, and recently became the second largest video site in the U.S. behind Google.
Keep in mind that Facebook's own official traffic numbers differ slightly from the comScore data, claiming closer to 550 million worldwide unique monthly visitors. No matter how you score it, the audience is a massive one and the site's popularity continues to spread across the globe.