Digital ad spend will total $61.5bn (£38.8bn) this year as total ad spend reaches $442.9bn (£279.2bn), and will continue to grow as a percentage of total ad spend, according to the report.
The Publicis Groupe-owned agency claimed digital will account for 16.5% of all ad revenues in 2012, up from 12.8% in 2009.
Paid search is driving online ad revenues and will account for 51.4% of them (£50.6bn) in 2012.
Display advertising dipped slightly between 2008 and 2009 but is expected to make a recovery before 2012, when it will account for 33% of all online spend.
Mobile social networking will become more important to advertisers as user take-up of services such as Facebook Places increases.
“New formats, especially video, mobile and social media, should help mobile’s share of internet spend return to 33% by 2012,” said the report.
“Between 2009 and 2012 we forecast mobile advertising to grow by an average of 44.3% a year, while social media advertising grows by 31.2% a year, compared to 14.6% a year for the internet as a whole,” it continued.
The announcement is Zenith Optimedia’s fourth consecutive quarterly upgrade in global ad spend, although its prediction for 2011 – 4.6% annual growth – represents a minor slowdown in total ad spend.
This story first appeared on newmediaage.co.uk