We intend to have prefinished wood floor installed in our living room. However, the room receives bright sunlight for about half the day. I am worried that if I move a rug after a year or so that I will see a difference between the formerly covered area and the rest of the floor. Are any of the prefinished varieties apt to be better than another when it comes to fade-resistance?

Many of the good prefinished flooring companies now have UV inhibitors in their finishes. While it won't stop wood from changing colour, it will slow it down a lot. I know that Mercier, Mirage and Lauzon have their versions.
The finish of species they want to change don't have inhibitors though.
Hope this helps.