I can't say I can complain about the speed of leveling, but for an mmoRPG, it is quite ridiculous. I completed not even half of Hyjal and all of Deepholm lvling from 78-85 on a recent alt, that's not even seeing 1/3 of the content in that span. Another tank alt has done maybe 15 quests since htting 20, and is almost at 80 now. It's incredibly easy to lvl now, and very little of the content is seen. If you do an instance while lvling before Northrend, you've already outleveled the zone you were in when you Q'd. WoW isn't an MMORPG anymore, it's lost it's right to call itself an RPG.