According to the Wall Street Journal, Facebook.com and Web sites published by companies like Conde Nast Publications and Glam Media Inc. have more than half of their visitors coming from outside the United States, though many have not yet recognised this as an opportunity, Bloomberg reported Thursday.

Sites with a majority of overseas readership sometimes only receives five percent of their revenues from these customers, according to comScore and industry analysts, the Wall Street Journal reported.

The paper pointed out that Web sites such as the Drudge report and Sony's Crackle are outsourcing advertising sales to local companies to increase ad revenues, according to Bloomberg.

In the past, traffic from abroad was very niche and non U.S. companies were less likely to invest in Internet advertising - so publishers ignored the opportunity, the Wall Street Journal added, according to the Bloomberg report.