"As consumer behaviour and time spent online rapidly shifts towards mobile, we expect advertising dollars to follow," said JP Morgan analyst Doug Anmuth. Social media is a "key driver of brand advertiser spend due to its large reach and highly targetable user base," added Anmuth.
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eMarketer projects digital ad spending to increase another 15.1 percent in 2013 for a total of $118.4 billion. That number represents a 21.7 percent share of advertising spending across all media in 2013, and by 2016 it is expected to surpass 25 percent. At the end of last year North America accounted for 39 percent of all digital ad spending.