babidy: I feel like it would be a little wierd if people on the upper decks could just look over the side of the ship and see you trying to relax in private
I don't know if they can see you from above, but the dividers between the balconies do have some space between them and the next cabin. Sometimes reflections can be seen in the glass doors as well.
I was doing a little private sunbathing on my balcony and I heard giggles from next door. It was the neighbor's 12 - 14 year old boy. I guess he got a show, and was doing his best to spy, but it did put me on alert that you can be seen.
Keep in mind that when in port, if you are on dockside, you will be on display. The ship docks early, so if you leave the curtain open for the night view, you might have an audience.
I like to have the sun come up and fill the room, so I figure if someone has telescopes, or whatever, they can have their show and I could care less. I guess I would feel differently if I was some celebrity and they were taking pictures with those telephoto lenses to put in a magazine or something.