Reports are coming in that Blizzard's Battle.net online gaming service has been taken down for Iranian players, following United States trade restrictions and economic sanctions that prevent Blizzard Entertainment, the game's developer and publisher, from doing business in the country. Users will, unfortunately, not receive refunds or compensation at this time due to the trade sanctions, though Blizzard has not ruled out the possibility of the MMO coming back to Iran if they are able to bring it back in the future.
A Blizzard representative posted the following message on the official forums:
Our team has been watching this thread closely, and we understand the desire for more information about this situation. Blizzard Entertainment cannot speak to any reports surrounding the Iranian government restricting games from its citizens.
This also prevents us from providing any refunds, credits, transfers, or other service options to accounts in these countries. We apologize for any inconvenience this causes and will happily lift these restrictions as soon as US law allows.
It seems that the game had already been down for Iranian players for several days before Blizzard issued a statement. Battle.net serves Blizzard's Warcraft, Diablo and StarCraft games, though it's unclear at this time if every single one of them is no longer accessible in Iran, or just Blizzard's newer games.
This is one of the few times where we've seen global politics and social conditions get in the way of a game, especially one as big as World of Warcraft. Hopefully, if it's at all possible, Blizzard will be able to sort something out quickly and bring those players back online.