Large guilds face a certain number of unique challenges. Beyond the usual demands of leading large numbers of players, guilds with memberships greater than 500 have an unfortunate tendency to break the guild interface. Up until now, this has been more of a nuisance than anything else -- Blizzard has never imposed a hard cap on guild membership. (WoW Insider's very own guild, <It Came from the Blog>, stands at 1,100 members, for example.)
Blizzard was keenly aware of the problems that these large guilds suffered, promising earlier in the summer to address them for Cataclysm. Well, not-so-great news, members of giant mega guilds: Blizzard is effectively throwing in the towel on large guilds and imposing a hard cap of 600 members effective the moment patch 4.0.1 goes live.
While the official blue post by Mumper says this will have no effect on 99.9 percent of guilds, this move could effectively devastate the remaining 0.1 percent. The full text is available after the break.