The top five US web properties in October 2012 were Google (189.7 million unique visitors), Yahoo (169.7 million), Microsoft (169.2 million), Facebook.com (149.1 million), and AOL (114.2 million). This is according to the latest data from comScore's Media Metrix service. In addition, among ad networks and buy-side networks, Google Ad Network ranked #1 with a 93.7% reach of Americans online.
Source: Cynopsis Media, Nov. 26, 2012
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