You’re Better Off Working at Starbucks Than Running a Social Network -Om Malik

Peanut Labs, a company that couldn’t find a business as an also-ran social network, says "The CPMs (cost per thousand advertisements) are so low it’s really hard to build a real business unless you have several billion page views and your own sales team. Social networks get 5 to 10 cent CPMs, and less outside the U.S. At one point we were averaging 3 cent CPMs. We figured out if we all got up and worked at Starbucks instead we would make more money as a company than selling 300 million impressions a month of ad space"