Are you worried about the D800's build quality?

Not at all, 6 months usage and no problems, I do not go out of the way to mistreat my camera but I have to have it ready at all times, if I am on foot it is round my neck switched on, if it rains a plastic supermarket bag provides temporary protection, if I am in the car is sits on an old travelling rug in the boot, I do not own a camera case as such, I have the camera with my spare lens in a pouch. My d100, d200, d700 have all been used the same way and all are still working to this day. Whilst only an amateur I consider my cameras to be a tool to allow me to enjoy my hobby, if it  should break I will get it fixed but I am not going to go through life wondering if it will break in. 12 months time, life is too short for that type of mentality !