TechCrunch
Alexia Tsotsis reports that social sharing service StumbleUpon sent 700 million Web pageviews to other websites last month, up from 400 million in December 2009.
On Monday, StumbleUpon CEO Garrett Camp tweeted that the site had recently surpassed Facebook as the top social media referrer in the U.S., according to measurements by StatCounter. This gives StumbleUpon an edge, with 43 percent of all social referrals, compared to Facebook’s 38 percent.
StumbleUpon has not received as much attention as newsrooms first gave to Digg, and more recently to Facebook. For one reason, the discovery of links within the site is, by design, largely random. Readers pick a topic of interest and are then served up Web pages recommended by other users. While obviously popular with consumers, that kind of serendipity, with an unclear return on investment, does make it difficult to judge how much staff attention to devote to it.
But as I noted recently, the service is free, people appear to be using it, and the potential upside is the aforementioned 700 million monthly pageviews. If you haven’t paid attention to StumbleUpon attention to recently, it is worth checking out again.

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