I once had a really great opportunity to speak with a CM whose job it was to determine and maintain the "props" and decor of the buildings in the Magic Kingdom. For instance, he was working in Harmony Barber Shop to be sure that the curtains still looked "new" and authentic for that time period. But the thing that was most intriguing is how much money and effort Disney puts into maintaining the historical and "theme" accuracy of the building decor and props.
One example: There's a section of Adventure land that sticks up over the Frontierland roofs and can be seen from Fronteirland. This section (which has tiki masks on the Adventureland side) has been decorated with a steer skull or some such on the Frontierland side so that it doesn't look out of place.
Also: There's a wireless tower by the Animal Kingdom. In order to make this "be part of the background," Disney put fake leaves and branches on it to make it look like a reeeeeeeeeeeeeeeeeally tall tree.
Anybody ever have the chance to talk to some of these CMs or have any other examples of really good historical attention paid to decor? I love that stuff!