On my Shaman, I barely saw Netherstorm before 70, and went up there way after I'd hit the highest level to go looking around for cash. And there are lots of fun quests to do up there, too. Shadowmoon Valley was another one that I didn't actually quest in for a while after 70, but now that I've done it, I'd say that it should actually be a priority ASAP-- there are a ton of terrific quests in SMV, not only for lore's sake, but just really well-done content as well.
When you hit 70, what areas did you head towards to continue questing in? And what areas did you "save" until you were as powerful as you could get, and reading to have fun instead of just grinding?