While attention in recent months has focused on marketing to consumers in Second Life--where Coca-Cola, IBM and Intel build "islands" to connect with like-minded people--virtual worlds targeting kids and teens seem to draw in far more traffic to their sites.

By 2011, an estimated 53% of U.S. children and teen Internet users will visit virtual worlds--up from 24% this year, according to eMarketer. In the report released this week, the research firm forecasts that 87.1% of U.S. teenagers will go online at least once monthly in 2011--a slight jump from 76.4% in 2007. Overall, children and teenagers will make up 18.2% of U.S. Internet users this year, basically flat from 2006.

"Advertising is part of the overall experience in child- and teen-oriented virtual worlds," says Debra Aho Williamson, senior analyst at eMarketer. "Unlike in Second Life, where marketers have built vast islands that avatars must visit to interact with the brand, advertising is part of the overall experience in virtual worlds for children and teens."

The Walt Disney Co.'s recent $350 million purchase of Club Penguin, a virtual world for kids, remains ad-free for now--but gives the media company a method to market its own products and services.

Disney also owns the virtual world Toontown Online and Virtual Magic Kingdom. There are plans to create sites based on "Pirates of the Caribbean" and Disney's Fairies franchise, which Williamson says builds off DisneyFairies.com, where girls design fairies and decorate homes.

Aside from Disney, Viacom and Warner Bros. have aggressive marketing plans for virtual worlds aimed at kids and teens. Viacom continues to invest heavily in TV-themed platforms, especially related to MTV. The network has introduced Virtual Laguna Beach, Virtual Hills, Virtual Pimp My Ride, Virtual Newport Harbor and Virtual Real World Sydney.

Warner Bros. will launch T-Works in early 2008. The ad-supported virtual world will let users create avatars based on cartoon characters, which they can repurpose across the Web.

Marketers wondering where kids hang out online should consider virtual worlds BarbieGirls.com, Webkinz and Stardoll, according to Williamson. Sites offering a virtual world for avatars have seen huge increases in traffic over the past year, according to comScore Media Metrix.

Two new sites that have gained significant traffic this year are Mattel's BarbieGirls and Nickelodeon's Nicktropolis. By July 2007, BarbieGirls had 1.1 million U.S. unique visitors and Nicktropolis had 2.2 million--just four and six months, respectively, after launch.

In the education-aimed world of Whyville, kids buy virtual Scions and learn about auto financing. One marketing promotion launched by the Centers for Disease Control and Prevention educated children about staying healthy.

During the promotion, some avatars randomly became ill and had to find a local CDC center to get virtually inoculated. In the process, the avatars learned why they got sick and how to live a healthier lifestyle.

As more kids and teens spend time in virtual worlds and marketers create campaigns for those environments, ad spending will likely increase. That's good news for advertisers of virtual worlds because most can provide detailed information on how users interact with brands, including how many visited a specific area, as well as how many wore or held a product. The bad news is it may be difficult to sort out the numbers to determine what it all means, Williamson says.

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