Architectural Perspectives 88 Published by the IEEE Computer Society 1089-7801/08/$25.00 © 2008 IEEE IEEE INTERNET COMPUTING 3D Social Virtual Worlds Research Issues and Challenges Adel Hendaoui • University of Lausanne Moez Limayem and Craig W. Thompson • University of Arkansas T he advent and success of 3D social virtual worlds (SVWs) reveal challenges worth ex- ploring for both researchers and managers. In his famous science-fction novel Snow Crash, Neal Stephenson envisioned the Internet evolv- ing into what he called a “metaverse,” a 3D vir- tual reality (VR)-based space in which people interacted and communicated with each other through their avatars (graphical representations of themselves). This is a far cry from the early text-based multi-user domains (MUDs) and MUD-object oriented (MOOs), in which a single character rep- resents a user. Virtual worlds have since evolved into sophisticated 3D interactive systems, such as massively multiplayer online role-playing games (MMORPGs), through which millions of people chat, cooperate, and compete with each other through their avatars. Beyond the entertainment and game-play features, virtual worlds are evolving toward Stephenson’s concept of a metaverse in which social and economic interactions are the main drivers. Currently, one of the best examples of this evolution is Second Life (www.secondlife. com), an SVW in which people (called resi- dents ) can communicate, collaborate, and buy and sell not only virtual goods and services (such as clothes and real estate) but also real products through their customized virtual spaces and avatars. Unlike most prior virtual worlds in which content was designed and managed by software specialists, Second Life developers have added an important feature: enabling users to build and personalize their avatars, private virtual spaces (lands), and objects (houses and clothes), through a powerful and easy-to-use interface. In addition to text-based chatting and instant messaging, developers also recently added voice communication capabilities that are opening in- teresting opportunities for learning and train- ing applications. Second Life’s population has grown from 64 acres in 2003 to 65,000 acres today and from 2 million residents in December 2006 to more than 9 million today. Roughly half a million users visit Second Life regularly (www.information week.com/news/showArticle.jhtml?article ID=201500141). Interestingly, residents spend more than a million dollars every day — this world might be virtual, but the money is real. Current business transactions are performed in a virtual economy, letting users convert real money into a virtual currency, indexed by an exchange market managed by the developer’s online platform. In other words, users can buy and sell virtual money at any time. Moreover, well-known companies and banks are going “in-world” (inside Second Life) to advertise and eventually sell real products and services, either by building virtual stores or putting a link inside Second Life to their traditional Web sites. Simi- larly, universities and educators are setting up lectures and classes in Second Life. Recently, the Swedish government opened an of fcial repre- sentation in Second Life, and French politicians promoted their presidential campaigns in-world (www.washingtonpost.com/wp-dyn/content/ article/2007/03/29/AR2007032902540_pf.html). Key Research Issues According to Gartner Group, “Eighty percent of active Internet users will have a ‘second life’ in the virtual world by the end of 2011” (www.gartner. com/it/page.jsp?id=503861). Similar to how the Internet expanded, we can expect SVWs to grow further, becoming a huge network of intercon-