Your guidelines: While this is Azeroth as if it had come to life, you are not your character –- this is the real-world you who's slipping into Azeroth. For the purposes of faction balance, you may assume that you appear to be the appropriate faction and race to be accepted by the inhabitants of the city or land you choose to visit. You can also communicate with the residents.
However, aggressive monsters will remain dangerous to you, and since you are real you and not your character, we don't recommend choosing a zone where you could be attacked by anything at all. (Unless, of course, you're actually qualified to battle these creatures yourself -– in which case, do send photos to email@example.com.) It's probably not a good idea to try stepping into a general zone or instance, unless you're certain you know a safe spot. But what about a city? A quiet fishing hole out of aggro range? A sightseeing tour via zeppelin, or a boating expedition along the shores of Krasarang?
Your advantage is the gift of instant materialization. Wherever you'd like to go, there you'll be. If you'd like to spend the afternoon reading under a tree on a floating island in Nagrand, we can make that happen. If you'd like to party in Goldshire, we'll get you there without braving wolves, spiders, and bandits (although what you'll have to brave once you're there is up to you). You can travel about only if the real you could manage it using Azeroth's usual modes of transportation.
What would you like to see? Who would you try to meet -- and do you think you could talk your way in to see them?
Where would you like to play hooky in Azeroth today?