According to this article from M-Net, Symantec, an internet security company, has begun targeting MMOs, such as Second Life and WoW, as potential outlets for criminals to launder money. Essentially, the article claims, that given the large amounts of basically unregulated transactions that occur in these worlds, it would be easy for dummy accounts to be created, for criminals to put money into these accounts, transfer the money in game, and then cash out in a different currency, all without being tracked. In addition, Symantec believes that much of software released to alter the interface of MMOs is laced with malicious programs designed to mine data and track keystrokes.
World of Washcash
It will be interesting to see if these fears are founded. If they are, who is going to stop it: the developers? the government? the players? It would be a jurisdictional nightmare if criminals in Russia laundered money through Second Life and cashed out in Hungary. Perhaps we should look into a VICJ - a Virtual International Court of Justice.