Here are the bugs i have found so far in icecrown citadel:   
10 Normal: 
Blood Prince Council -- Prince Valanar - http://www.db.pandawow.me?npc=37970 unless he is the one that dies first there will be no loot 
Lich King    -- http://www.db.pandawow.me?npc=36597#abilities   the spell http://www.db.pandawow.me?spell=70337 if it jumps even once to another player the player it jumped to will intantly die during remorseless winter   
25 Normal   
Blood Prince Council -- Even after all three princes are dead none of the gates open and you are stuck in their chamber   
10  Heroic 
Lich King --- After you are absorbed into frostmourne and after you get out you can't move and u will die to him     
All Difficulties: 
Gunship battle cannot be started   
http://www.db.pandawow.me?quest=24749 Unholy Infusion After you drink to mutate you have no model , here is the thing you mutate into http://www.db.pandawow.me?npc=38285  half of its spells are missing it only has mutated slash and http://www.db.pandawow.me?spell=71516 the spell you need to cast to infuse its missing the spells http://www.db.pandawow.me?spell=70360 http://www.db.pandawow.me?spell=70405 
http://www.db.pandawow.me?spell=70539 it auto regenerates ooze so its ok but after its 20/100 it auto resets to 0 so you CAN'T infuse shadow's edge