Ajax (Asynchronous JavaScript and XML) allows sites to change some or all of a page’s content without forcing users to click to another page. GoogleMaps employs this technology to produce information bubbles above locations.

So, when content changes on an Ajax site, new page views are not recorded. Page views, however, are, for now, the way advertisers determine the value of websites. “If you are a publisher that is really focused on user experience, [Ajax] does make sense,” said Julian Zilberbrand, associate director of digital operations for MediaVest. “But it potentially severely limits the ad opportunities you have.”

This issue has already reared its head in a different way. Last year, when it was reported that MySpace had topped Yahoo in page views, Yahoo protested that its page views had dropped because of its use of Ajax.

However, new traffic measurement technology is on the way. Nielsen/NetRatings yesterday launched new traffic calculating technology that will be able to view users’ time spent on particular sites.

Websites worried about losing ad content, then, might want to wait on picking up on the Ajax trend until new measurement tactics are firmly in place.

Source: Poytner Online and Media Week