eMarketer: Global Ad Spending On Facebook Will Reach $4B By Year’s End

eMarketer predicts that social network advertising will account for nearly 11% of all online ad spending in the United States by the end of this year. According to the research firm, US marketers will spend a little over $3 billion to advertise on social networking sites this year, up 55 percent from the $1.99 billion advertisers devoted to social networks in 2010. eMarketer projects this number