If like me you were wondering why there is an ever-so-slight pause between the moment you click a folder in OSX and the folder showing its contents, then I have an answer. It's because in OSX (well,at least in Leopard), there is a setting called "Spring-loaded folders and windows", which actually lets you define the length of this delay. It seems slightly odd to me that anyone would want to artificially slow down their computer, but if you are so inclined (or if you want to turn the feature off altogether), then swoosh your mouse over to Finder / Preferences / General, and play around.
Turns out I was wrong. This function controls the speed at which the drag-and-dropping of folders works. Still, playing with this setting should speed up your day-to-day work. Thanks for pointing that out @abeboy!
