I just found out that you can fly around in the Ahn Qiraj zone as a ghost, I've not tested with other races than nightelf tho'.
Background:
Me and my friend went to explore the new Ahn Qiraj zone and found out to our surprise that the instances still existed. We entered AQ40 and I somehow managed to die on the first boss guarding the entrence. <.<
As I went back to the instance to ress I found out that as soon as I entered the AQ zone I was able to fly, as a wisp. I tried to leave the zone, but that'd remove my ability to fly.
You can get to Uldum from AQ, flying, but as soon as you enter the zone you'll get teleported out to Uldums main entrance. I have yet to explore the possibilites some more tho'.
This might work with other zones aswell, just found it.
I'll provide with a video soon.
YouTube - AQ flying glitch