Blizzard released a whole bunch of new Karazhan artwork, all of which was created recently. They didn't do this for just one boss either, but they appear to be doing it for all of the bosses in the dungeon, which is an expensive / time consuming thing to do just for nostalgic kicks.
I'm interpreting this as a pretty heavy clue that Karazhan might be returning in the future, either as a raid or (my guess) a pair of 5-man dungeons. I could be totally wrong, but I think it's a reasonable prediction given the amount of attention they're giving it.
What, if anything, do you think Karazhan will become? A new raid? Two or three heroic dungeons? Something else?
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