I just hit 70 Friday night in Nagrand not even halfway done with the quests in there. I did every quest I could with my 4 box shamans, collections and all. I did this to be able to quest after 70 for gold so that I could get my epic flying mounts. I have to say, doing all the "trick or treat" buckets was a nice little chunk of exp too. As for instances, when I hit 66, I soloed Ramparts, Blood Furnace, and Underbog (last boss here sucks), but otherwise I quested.