We shouldn't be surprised, they did it last time
Following the example they set with the Burning Crusade, Blizzard has said that Icecrown Citadel - the top raid instance in World of Warcraft: Wrath of the Lich King - will not ship with the expansion. It will be added to the game with a later major content patch.
As if we didn't really see this coming -- just like the Black Temple with Burning Crusade, Tigole confirmed for sure that the last instance of Wrath of the Lich King will be pushed off past release to a content patch (likely 3.1 or 3.2, if we had to guess), which means we won't face Arthas for a final showdown when the expansion releases. Of course, there'll be plenty to do anyway -- besides all of the other 5man instances, there'll be Lake Wintergrasp to mess around with, and of course Naxx and Zul'Drak will be in and ready to go. But those looking for a Lich King resolution will likely have to wait -- while we'll see plenty of Arthas, we won't actually face him until the Icecrown content patch.
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