If your considering Automating parts of your house in the future ie more lights in the house, appliances (handy in the cinema setup), alarm, heating etc. then it maybe worth you looking at X10 equipment.
what your describing is what they call Ramping of the lights. You can fit a light module either behind the switch or put in the ceiling/floor space and be able to control it via the switch or remotely. As well as other items.
eg. my setup will allow me to turn on my Cinema Setup with one button. What happens is Screen comes down, Projector turns ON, AMP turns ON, Subwoofer turns ON and lights go OFF. This is all from one button.
another excellent feature i have, when watching TV, Movie, DVD etc and the lights are obviously OFF, if someone comes to the door i have a senosor outside, it detects them at the door and it sends a signal that pauses whatever im watching and turns the Lights ON to a Dim Level i have choosen. (also works if i press pause on the remote). I go the the front door grab my pizza etc, come back sit down hit play. The lights dim out until OFF and then the movie continues.