Joanas Guide worked fantastic for my hunter. I'd already leveled my priest kinda randomly on my own. I got my hunter to 70 super fast. It is a very fast way to level. Basically he tells you the order to do quests in, where to set your hearthstone for strategic hearthing and efficient quest lines to do. If you want to level a single toon at a time, very fast, this is the way to go. (So if you're making your first level 70 pally/mage for boosting the rest of your toons, this might be a good idea).

If you're multi-boxing, many gathering quests will drive you nuts. Now that I am boosting and multi-boxing, I don't use the guide anymore.