The results were as expected. Until recently, however, many of the most popular sites were shy about accepting the sort of ad that Procter and others most wanted to buy. That began to change last fall, not coincidentally as Internet companies started to fail. Cnet and iWon also created big TV- like ads. Increasingly, sites are also mimicking America Online and permitting ads that pop up in new windows over their pages.
More people complain, too.
If it gets too high we worry. The biggest source of complaints, she said, is the same advertisement popping up too often. So now the site limits the frequency of such ads. General Motors is testing an alternative format that superimposes animated images right over Web pages. If a user clicks on it, the image stays and more information is offered.