Johnathon Suker <firstname.lastname@example.org> commented that my technique of copying new System Folder files over the old ones and then moving them all back again could lead to trouble if some old and unnecessary System Update file or something similar was included by this process. I should have mentioned that I always go through the resulting folders and manually scan for files I know won't work with the new System. A slower method might involve opening both the old and the new folders and manually moving (from the old to the new) just non-Apple files that you know will work. [ACE]
Expose Shortcut for View All Windows
In Expose mode in Snow Leopard, press the Tab key to view all windows belonging to one application (equivalent to pressing F10 or Control-F3 on recent laptops). Press Tab again to switch between applications while remaining in Expose. You can also click an icon in the dock.