Google: 1 billion served, monthly.
Google has reached an unprecedented milestone as the world's first Internet company to claim over 1 billion unique users in a single month on its websites.
According to data from comScore (via the Wall Street Journal) during the month of May, Google-owned websites, including its search engine, email service Gmail, and video-sharing site YouTube, among others, notched more than a billion unique visitors, an 8.4 percent increase over the previous year.
Google boasts approximately 100 million more users than the next most popular company on the web, comScore reports. Microsoft's sites, with 905 million unique visitors, were the second most-visited destination on the Internet and Facebook came in third with 714 million users, up 30 percent from over the previous year.
Google's number of unique visitors has more than doubled in the past five years, from 496 million unique users in 2006, when comScore began measuring sites' unique visitors, to over 1 billion today.
Research by Hitwise, a firm providing online competitive intelligence, released in December 2010 found that while Facebook had topped Google.com as the most-visited website of the year among U.S. users, when the share of all Google-owned properties was taken together, Google could still claim a greater share of visits (9.85 percent to Facebook's 8.93 percent).
The Wall Street Journal explains comScore's methodology:
ComScore’s estimates are based on its “global measurement panel” of two million Internet users, similar to how Nielsen measures television ratings. ComScore refines the estimates with “page view” data that it receives from more than 90 of the 100 publishers of Web content, but not from Google.