... and is expanding at double-digit rates, according to the latest quarterly forecast from Publicis' ZenithOptimedia Group. The agency estimates that Internet ad spending will expand 10.1% in 2009, an increase of more than 1.5 percentage points over its last forecast in April. "Its familiar virtues of transparency, accountability and flexibility have proved even more attractive in a recession than ever," the Publicis shop writes in the new report, released early Monday morning. Based on current trends, the agency projects Internet ad spending will rise to $56.8 billion this year, or 12.6% of the global advertising economy. That means the Internet will pick up more than two points of worldwide advertising share, this year, and its momentum is only expected to accelerate. "By 2011 we expect it to account for 15.1% of all ad expenditures, up from 10.5% in 2008," the report predicts. "Most of this growth will come from paid search, which is an ideal method of reaching consumers looking for bargains. In the U.S., we predict search advertising to grow 20.0% in 2009, while traditional display grows 3.0% and classified grows just 1.8%." More ...