The plaintiffs claim damage as a class as third-party-beneficiaries on the understanding that the WoW ToU and EULA are supposed to protect players as a whole (and Blizzard) against just this sort of thing.
While third-party beneficiary contract claims are generally pretty hard to argue, Blizzard supports the class-action, and that could make all the difference if they are willing to come to the party.
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Correction: Okay, complete screw-up. No, IGE isn't a sponsor - Weblogs, Inc. and Massively has no connection to IGE at all. None whatsoever. This is the hazard of doing too many things at once. I got confused, and made a mistake. You may now throw fruit and vegetables at me. Hopefully that's my one embarassing screw-up for the week.