The product is called "the eXplo platform." It's a framework for 3D online environments running on mobile phones. Its features include customizable personal spaces (essentially player housing), messaging, photo sharing, shopping, and games. A few days ago the CNET News Blog took a look at S! Town, a product based on the platform. Initially released in Japan, it's headed to North America and Europe and will feature Facebook and YouTube integration for American consumers.
Look for S! Town in North America and Europe in 2008.