crap, actually, i just remembered i went from 61.75 to 68. At that point i was so tired of it i just went and did northrend quests till 71. Still, about or under 2 hours a level in the 60's is pretty damn fast imo.
I ground rhino's just outside of warson hold. The longest one is 70 to 71, you run out of quests without having to delve into the collection shit that's a nightmare (if you started at 68)