Online advertising revenues in the U.S. seem to be stabilizing. The Interactive Advertising Bureau (IAB) and PricewaterhouseCoopers released third-quarter figures showing that online advertising in the U.S. approached $5.5 billion, up 1.7 percent from the second quarter of 2009, but still down 5.4 percent from the same quarter a year ago (which is in line with the losses during the first half of the year).