Despite growing pressures on global advertising dollars in general, ZenithOptimedia’s optimistic outlook for online ad spending is undiminished, projecting that the category will surpass radio ad dollars in 2008 and the amount spent on magazines by 2010. ZenithOptimedia will present its latest forecast early Monday morning at the UBS Global Media & Communications Conference; AdAge has a preview. Some of Zenith’s findings include:

—Internet ad spend:  Global online ad spending will rise 24 percent to $44.6 billion from $36 billion. Online’s share of the world’s ad market will increase to 9.4 percent from 8.1 percent.  Zenith expects online advertising to achieve three milestones within the next three years: it will overtake radio ad spend in 2008; comprise a double-digit share of global advertising in 2009; and surpass magazines in ad dollars by 2010, with 11.5 percent of total ad spend.

—Europe’s online ad growth: Britain,Denmark, Norway and Sweden are the only four places where online ads account for 15 percent or more of total spend, according to the TimesOnline.  But Zenith’s projections say that will change by 2010, when the internet will comprise more than 20 percent in each of the same four markets and more than 15 per cent of the ad spend in ten other countries.

—Overall: Zenith is predicting that advertisers will spend $195 billion on ads in North America next year, a gain of 4.1 percent compared to 2007. Globally, ad expenditures will reach $486 billion in 2008, a 6.7 percent rise.

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