So you're standing in Tempest Keep, preparing for your third take on Kael'thas for the night. Suddenly, you hear a loud crash in the next room, where your husband is putting your daughter to bed. Do you tell your team "GTG" and hearth, or do you run out of the room instantly and leave your character where it is? What if it's your dog and not your child? What if it's a phone call?
There's a debate on this very subject going on in the Raids and Dungeons forum. Belak of Crimson Fury asks the simple question of whether there's any way to kick a raid member who suddenly took an extended AFK for an emergency so they can get a 25th player in the instance. The forumgoers tell him that sadly, there's nothing he can do about it. Several raiders noted that they don't believe in such things as an emergency AFK without warning, noting that it takes less time to Alt-F4 than it does to get out of your headphones for Vent.