The Internet Advertising Bureau and those mysterious briefcase-handling gents at PricewaterhouseCoopers have released IAB’s Internet Advertising Revenue Report for the first half of 2009, which reveals that revenue stands at $10.9 billion–a 5.3% decline from the same period last year. The economic downturn no doubt played a role in the slide, but IAB president/CEO Randall Rothenberg assures us in a statement that “Interactive is one of the advertising sectors that has been least affected.”

Search and display were yet again 1 and 2, accounting for $5.1 billion and $3.8 billion, respectively, of all online ad revenue in the first six months of ’09. You can read the full report here.

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