I'll probably never go to the USA so that would not be an option.
The way I get rid of my points at the moment and get some money back is if I know somebody who is going away somewhere, I book a room in the Marriott for them and they give my 50% of what they would have paid so it works out well.
The option for the camera was just put forward as somebody might have been interested in a new camera at a much cheaper price that what they would pay in a shop. I can see people probably won't be interested so I'll continue with the room bookings and when the D600 is available I'll see then if I have enough points still which I doubt it. The D300 was about 650,000 points and the D7000 around 360,000 I think.