Well, it's right that we relate things spatially, we "know" where the buttons to the light bulb are, and we always expect them to be there. While this definitely does make sense, and it would also be nice to have all things spatial on the computer screen, I somehow don't like the idea.
Our "view" is limited by the size of the computer screen: 17" or 19". This much a window is too less to do things spatially. It does make sense in real world, since we work in 3D and think in 3D. Our hand automatically reaches out to the gear lever on the cars, our fingers reach out to the right keys on the keyboard with some practice, but this is in the world that's not limited to just some screen-sized resolution. Also, the "objects" we deal with, cars, keyboards, doors, etc., are different and our brain remembers and maps the various "controls" to the right objects.
However, it would be very taxing on our brain to actually map various folders of a single object -- "/" or "/home" -- in a 17" diagonally-spaced window. The screen is going to run out of unique new start-locations for all the folders we have, and access. So our brain not only has to remember the namespace object to the folders, it also has to have a hash of the co-ordinates of the screen which maps to the various folders that are opened at those co-ordinates.
I haven't used the Gnome spatial nautilus yet, but I've experienced the spatial explorer by way of Windows 95; and it sure wasn't a pleasant experience.