I think many people already realize that online gaming is going to be a giant catalyst for bitcoin adoption, especially as an MMO in-game currency. It is only a matter of time before you buy your armor and weapons with btc, loot monsters for btc, and can cash out your btc. Imagine the day when you battle another player, loot his armor, sell it, withdraw, and make your car payment.
I project that in a few years btc use in virtual economies will surpass btc use in the "real" economy. If there is anything btc would excel at, it would be for in-game currency. Adoption in virtual worlds could take bitcoins to an entirely different level. Odd that no one is even talking much about this.
Sorry this will not happen.
This makes for a completely different game, the entire game economy has to be based on the fact that it's real money. Hence there is only two games with a real cash economy that I am aware of, the most popular being Entropia Universe, neither of which has a very large player base. Why? Well, people need to lose money for the game to go around, hence the incentive to actually play is alot harder to create. In Entropia the principal is pretty much if you get ahead of everyone else, you can make a small profit. Giving people virtual gold is not costing the company anything, giving out more bitcoins then they take in can't be done. Which is why games like WoW will remain dominant for a long long time.
Markets for virtual game currencies to btc convertions however will become more and more popular, and already exists.