iht.com: Interactive sites serve young Internet users, in particular preteen girls

jugendschutz.net

These sites, with names like Club Penguin, Cyworld, Habbo Hotel, Webkinz, Piczo, WeeWorld and Stardoll, run the gamut from simple interactive games and chat to virtual worlds where children can visit fantasy lands with mountains and caves.[...]
To make Club Penguin safe for children, the site uses a powerful filter that limits the kinds of messages users can type to one another. It is not possible, Merrifield [chief executive of Club Penguin] said, to slip in a phone number or geographic location, or to use phrases or words that would be explicit or suggestive. Other sites are also set up to minimize the threat of troublesome interactions or limit what users can say to one another.