> In this case the third party is Blizzard Entertainment, who can control the state and data.

And in the case of two Ethereum based assets, the third party is the Ethereum network, which can be forked to control the state and data (as it was after the DAO fiasco).

I think more importantly the integration with Ethereum network is done by third parties, so even if WOW hooks into eth, your eth assets are worthless without depending on blizzard to maintain that integration. So what was gained?

"And in the case of two Ethereum based assets, the third party is the Ethereum network, which can be forked to control the state and data"

ETH Classic still exists, but the community came to the agreement that forking was the best way to deal with the issue. The only person who lost on that agreement was the hacker. Where as Blizzard can do whatever it wants. Surely you can see how a forked blockchain was a more democratic process than a centralized database.

A company like Blizzard that might define ERC20WoWGold can fork the blockchain to try and alter a record on their contract, but it would have little effect.

A successful fork requires a consensus across the majority of developers and users in the network.