83% of US online shoppers are interested in sharing information about their purchases with people they know

"The survey results confirm that consumers are social with 83 percent of online shoppers very or somewhat interested in sharing information about their purchases with people they know. In addition, 41 percent would be inclined to join and be active participants in online communities that share information about their favorite products.
This information sharing impacts commerce as pre-purchase opinions from others influence buying decisions for 74 percent of online shoppers. Additionally, 73 percent agreed that "people like me" are the most trusted sources when making a shopping purchase. In fact, product recommendations from friends are almost twice as valuable as product recommendations from merchants (46 percent versus 24 percent) for their ability to influence purchases."
Source: Survey findings from Ripple6, 9th September 2009