A test version of the new program dubbed "image ads" was launched yesterday and is the latest development of its pay-per-click advertising scheme. The system allows advertisers to pay Google a fee, equal to their bids on keywords, each time a Google user doing a search clicks on one of their image ads.
The ranking of those advertisements is determined by both the price paid for the keyword and the number of clicks the add itself has generated. Last year alone the scheme generated around 95% of the company's revenue of close to $1 billion.
For the time being, the company will not be posting the image ads on its own site. Apart from the quality of its search engine, the lack of advert clutter on Google's site was a key driver of its initial popularity.
Google image ads are matched to a web page's content by the same targeting technology that drives AdWords' text advertisements. Because of this targeting, image ads should remain pertinent to the interests of a person browsing a particular content site. With image adds being restricted to 50KB in size (the text adds currently used are around 1-2KB), Google claims that it will not have a considerable effect on load time for most sites.