I'm beginning to wonder whether some are sleeping in their beds or are sitting in their Sealy Posturepedic foxholes waiting for "Charlie" to come through the wire.
Granted, any yahoo that would stand at the top of the stairs, shout "hey you" and then rack the slide for effect is probably long overdue for some kind of bodily injury.
That said however, in a dark 2 story house (home field advantage) where I have a bead on the welfare child who wants my flatscreen, jacking a round into the chamber from behind cover is probably the best of both worlds.
Depending on the size of the house, an intruder would be lucky to determine the general direction of where the sound of the gun was. I have surefires and such, but when defending my own house they are more of a hinderance than a help. I know where everything is, and what everyone in my family looks like at o'dark thirty in the morning. Shining some light all over the place is gonna give the bad guy a hell of alot better chance for a spin and shoot then me racking the slide.
Even if he does get lucky my index finger still moves faster than he can.
As for the sound itself... it seemed to get the attention of many a looter and pillager during the L.A. riots according to several agents I know. Based on my own personal experience, movie or not, its definiately a universal language, and people get real polite and seem to take instruction extremely well when that slide moves. Just my .02