Online advertising in Europe is set to double in both value and volume by 2012, according to a new study. Research group Forrester has concluded that the value of online ads will rise to $22 billion over the next few years, up from $11 billion last year, and that the market share of online advertising would increase from its current 9% to 18%. The U.K. is set to see the greatest rise, ahead of Germany and France. “After five years of dipping their toes into the online marketing waters, firms have come to realise that the net is a valuable medium for client acquisition, retention and market expansion,” said the study. Europeans spend more time online (14.3 hours a week) than they do watching television or reading, according to Forrester. Indeed, 36% of people who go online said they spent less time watching TV as a result, making the Internet a more and more vital ad market. 52% of Europeans are now regularly online. It’s anticipated that search engines will continue to dominate Internet ad spending, followed by display ads and e-mails.