1) Now this is not massive but it has its leveling uses - the creatures that walk along water atm (especially the ones with 4 legs and look like water crawlers) currently run on the water at normal speed. BUT if you engage in normal combat with them they are bugged and walk extremely slow, making for a stupidly easy kill for free xp.
2) on the quest Fog Wards in valley of four winds, if you activate the ward and drag tons of mobs to it and then use it. All of them will die and you will gain xp for all of them, you do not need to tag them. This didnt happen before and is quite nice if your a tank
Sorry there small, hope anyone can find these useful for leveling. enjoy