Blizzard announced this week, as Diablo 3 will come in the package with a House of auctions that will allow them to buy and sell items in-game, in the context of real money trading.
Each region will have a single market, in order to avoid any problem related to Exchange.
After selling an item, you will be able to withdraw money and use it in the real world, through a reputable third party companies that has not been announced yet, or want to use in another auction or other Blizzard game.
Blizzard will take considerable income through this new system: players will be charged with a Commission both for listing an item, as well as for his trading.
Diablo 3 will also have a second House of auctions, separate entrance, which will work only with virtual currency Gold, in which the listing of goods may be free.
Blizzard has announced that the third title of the franchise will require permanent connection to the internet, the decision will surely revolt on players.