There is rampant farming in these games with this kind of money involved

Sony Entertainment Online, maker of "Everquest II" and "Star Wars Galaxies," has taken steps to curb gold farming by providing its own Rohan Online Gold auction site where its players can transfer virtual property in real money transactions. 

The CEO stated in an interview that RMTs are "a billion dollar industry worldwide and we as game makers need to seriously work to handle it in-game about selling rohan gold. There is rampant farming in these games with this kind of money involved, it's not going away."

So although Sony Entertainment Online may retain all copyrights to the creative works within their virtual worlds, the company loosens its grip on the right to sell to reduce infringement and the cycle of one-upmanship.

Second Life

Linden Lab had a different approach. The Second Life community allows a uniquely high level of user interaction with the virtual environment compared to most online games.

There is an abundance of creativity and user originality beyond that contemplated in Midway Mfg, which warrants a deeper consideration of gamer rights in a finished virtual product. The Second Lab EULA unsurprisingly allowed gamers more intellectual property ownership:

"Subject to the terms and conditions of this Agreement, the user will retain any and all applicable copyright and other intellectual property rights with respect to any Content [the user] creates using the Service, to the extent [the user has] such rights under applicable law."