Everquest 2 is essentially a game set in a fantasy world (like Lord of the Rings) where you play a character such as a Wizard or a Paladin (like DnD). This game is played exclusively online, and your character "lives" on a server with thousands of others (and there are dozens of servers). Your character moves from a pathetic peon, running for dear life from sewer rats to a powerful behemoth, destroying even powerful dragons and giants. This takes HUNDREDS of hours to do, though. While doing it, you earn in game money to buy better equipment, housing and even pets.
These types of games (MMORPG's) have been around for many years now, and there has always been a "grey" market where someone will spend the hundreds of hours to create a character and then sell the right to play this character or in game money on ebay for hundreds and sometimes thousands of dollars. Officially, Sony(the makers of Everquest) has always opposed this grey market and has kicked people off the game when they were found using it.
But now Sony has decided, at least on a few of the servers, to make this an officially sponsored activity. People will be able to sell things in game for real life money, and Sony itself will oversee this market (estimated to be in the hundreds of millions of dollars!) and ensure people do not get ripped off (as previously that was quite easy).
Where this will go no one knows. Sweatshops in China with workers being paid pennies an hour to play Everyquest? Maybe. College students making a good side income creating and trading Everquest goods? Probably. Fascinating insight into human behavior, computer gaming and economics? Most definitely!