We knew that Internet advertising is on a strong upward trajectory. But now analyst firm eMarketer is predicting double-digit growth through 2015. Spending on online ads will hit $50 billion that year — that’s almost double last year’s spending figure.

The prediction, published Tuesday, comes a month after eMarketer nearly doubled its estimated increase for online ad revenues for 2011 to 20.2%, thanks to a surge in display advertising. U.S. online ad spending hit $26 billion in 2010. The new report assumes a continued growth in search advertising, but also in banner ads from large sites like Yahoo, Google and Facebook.

Video will continue to be the fastest-growing format in online advertising, according to eMarketer. Spending for video ads hit $1.42 billion in 2010, but will reach $7.11 billion in 2015. That’s because video “generates greater audience attention than other digital ad formats,” says David Hallerman, eMarketer’s principal analyst.

Another factor in the rise: a shift in local advertising from newspapers and Yellow Pages to online ads.

eMarketer’s figures are by no means the only ones. The IAB reported a 23% jump in online advertising revenues in the first quarter of this year. The IDC also estimated that global online ad spending grew 14.3% in Q1. Online spending is far outpacing increases in traditional advertising. Nielsen estimates global ad spending rose 8.8% in the first quarter, and TV advertising was up 11.9%. U.S. advertising was up 5.9% in the first quarter, according to Nielsen, which didn’t include online ad spending in the report.

Photo courtesy of iStockphoto, 123render

More About: banner ads, display advertising, emarketer, facebook, Google, IAB, idc, online advertising, search advertising, Yahoo

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