• by Jim Meskauskas , April 24, 2003

It was in 2001 when the IAB announced new ad guidelines for the first time since '96 for larger sized units for online display advertising. "Skyscrapers" measuring 120 x 600, rectangles having dimensions like 240 x 400, and 250 x 250 pop-ups meant ads could claim more territory on a site that was traditionally reserved for content, or worse, a multitude of tiny branded buttons and text links. The move was heralded by most of the industry as being "about time," since a lot of sites were already running ads of the kind the IAB was then endorsing.

Industry wonks also saw the change as important to getting more general market advertisers onto the web because they would now have ad units whose sizes lent themselves to greater creative opportunity. This meant better chances at conducting branding online. And it turned out that was true.

Last week saw the latest trend in online display advertising make its way into press releases and online news sources. Forbes.com, NYTimes.com, and CBS Marketwatch were among the notable publishers announcing that they would now start running as a matter of course what is being called a half-page unit.

If you haven't seen it, the ad unit is essentially a very large rectangular skyscraper whose dimensions are somewhere between 350 pixels by 850, depending on the site.

The idea for this kind of ad is nothing new, and it portends of things to come for advertising on most of the web.

But as the "bigger is better" arms race continues, important questions that marketers want answers to before putting their dollars on the web remain unanswered.

What does it mean to be able to now run these half-page units on quality content sites? We've all read the regularly sunny Dynamic Logic branding reports that suggest larger units have greater impact than smaller units, but what can advertisers regularly expect from their advertising if it consists of these kinds of very large ad units?

If I'm planning Print and I'm trying to decide which ad size to use given the dollars I have to spend, I can go to the shelf, grab Media Dynamics' Magazine Dimensions, and take a look at how one unit size compares to another. If a page, 4-color noticing value is indexed at 100, a 2-page spread indexes at 135, and a half-page indexes at 70, I am able to get a pretty good picture of what kinds of sizes are likely to have what kinds of effects on my intended audience. Yes, there are all sorts of other influencers, but at least I can tell a client what the trade-offs are regarding dollars versus ad sizes.

I'm actually a big fan of the ad unit and have contended for some time that more quality publishers adopt ad units like the half-page that Forbes.com, NYTimes.com, and CBS Marketwatch are now touting. But I have also always advocated that this be done in connection with a shift towards audience-based media currency rather than the blind gross impressions we continue to be stuck with. Only when sites start attaching these large units to unique audience and guaranteeing that audience to advertisers will the medium truly come into its own, and issues like reach/frequency, excess inventory, and clients never being able to see their ads on sites will start to resolve.

For now, the online advertising space just continues to super size without posting the calorie count. It is intuitive that bigger is better, but few marketers are comfortable going just with their gut. They should know what the impact on their health will be before taking a bite.