I agree with others who have said the control of the window shade belongs to the person who has the window seat. That is one of the perks of sitting there, just as one of the perks of sitting on the aisle is being able to stretch your legs out. If you want the shade down you should request a window seat.
For those of us who don't get to fly that often having the shade up is preferable. I enjoy being able to look out and see things down below, even just the clouds. And for ROADRUNNER who isn't opposed to reaching OVER and pushing the shade down, that is just rude! Do it to me and I'd push it right back up!!!