IDK - MoP doesn't have one spot that I would just love to be. If I had to pick a spot, I would likely choose the snowy peaks of Mount Neverest in KunLai Summit. Very peaceful way up there just flying around and picking snow lillies.
serenity falls and lake kittitata in the jade forest. i'd also like the black market ah area if it were a little bigger, and i could get away from the buildings. love the fog over the lush green trees and grass.