Virtual world advertising that works -- such as the Kool-Aid Man with jiggling ice cubes seen on WeeWorld -- integrates into the lifestyle of the world's avatars, says Lauren Bigelow, WeeWorld's general manager. Advertising that doesn't work includes logos slapped onto virtual world merchandise and, of course, plain static billboard signage.

"Standard banner ads in virtual worlds are a complete disconnect," says Debra Aho Williamson, an eMarketer analyst. "If you don't pay attention to banners online, why would you do it in a virtual world where there's so much going on around you? Anything that doesn't fit in with the world doesn't work."

"Pop-out windows pushing a product derail the user experience in virtual worlds," says Barry Gilbert, vice president and research director at Strategy Analytics. "One of the key things is to build unobtrusive advertising that's less in your face."

Bigelow agrees that pushing products is a losing proposition, while making branded products part of the user experience works best. Visitors to WeeWorld become avatars who buy clothes with WeeWorld currency, which paves the way for apparel advertisers to show their wares. Cover Girl successfully promoted its make-up by offering it for free to avatars, and Skittles candy offered hats, bathing suits, and skateboards that visitors donned. This strategy works because "it spreads," Bigelow says. "Once you get it, your friends see it, and they all become brand ambassadors."

Even advertising for less desirable products can work. A razor that was advertised in WeeWorld shined when it touched an avatar's legs. "It was the opposite of slapping a brand, it was integrating it into the things they do," Bigelow says.

What didn't work at WeeWorld was an attempt by an apparel manufacturer (that Bigelow declined to name) to simply stick its logo on clothes. "They applied old advertising techniques to a new medium," she says.

In some cases on Second Life, visitors have soundly ignored some of the stores that brands have created in the virtual world. Because the stores weren't properly integrated into the user experience, there was no reason to visit them.

In general, many marketers view virtual world advertising as being relatively new and untested. "What's the appropriate media for the advertising and how you develop effective and unobtrusive campaigns, no one has the answer for that," Strategy Analytics' Gilbert says.

Actually, WeeWorld would beg to differ.

Ken Liebeskind is a freelance reporter and copywriter who specializes in digital advertising.

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