WoW Insider writes:
"I'm always amazed when people hit 80 and then start wondering how to make gold. Sure, there are all kinds of money tricks floating around (playing the AH is always fun, and everyone has their own tips they've picked up), but quite frankly, the easiest and most reliable way to pick up a ton of money at level 80 is just to do what you've been doing: go quest. Blizzard has made it so that there's no way you've hit all the quests in Northrend when you've reached the highest level, so odds are that you've got at least one (if not two or three) untouched zones of quests to do. And as folks have discovered on the forums, there's a ton of money to be made there."