Enterprise 3-D virtual world applications have proliferated during the past several years. What began as fun and games is becoming a serious business with a lot of upside. A host of new, innovative 3-D virtual world applications have been introduced to the marketplace targeting the enterprise. Some of these applications have been created by established technology companies, such as IBM, Sun Microsystems and Nortel, while others are being developed by emerging players, such as Forterra Systems, ProtonMedia, Qwaq and Unisfair. This report profiles 14 key players and provides market forecasts for enterprise deployments of virtual world applications over the next decade.