It looks like a trade barrier has been put in place to protect the Korean gaming industry from competition from Facebook games:

The Game Rating Board (게임물등급위원회 Geimmul Deung-Geub-Wiwonhoe) (GRB) has blocked Facebook games in Korea. While I’m not much of a game player, this seems a heavy handed tactic. A game developer must hop through some pretty demanding, Byzantine hoops in order to get a game evaluated by the reviewers so I wouldn’t anticipate much relief if you live in Korea and enjoy games on Facebook. It is especially vexing as I am not aware of any game apps on Facebook which would be blocked if they were evaluated. What would the rating be for games like Candy Crush? Perhaps Facebook will negotiate to get their games cleared en masse on behalf of the individual developers, or perhaps they will just write Korea off. It will be interesting to see how this develops.

To Facebook’s credit they have been refunding people who live in Korea who spent money in a game, retroactive to 15 July:  [Korea Noodles]

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