Dimmer or brighter?
One reason often given for still using incandescent bulbs is the fact that the new energy efficient bulbs do not work with dimmer switches. To be honest, it's a fair point. The counter argument is that you don't need dimmer switches on your lights. The argument that comes back is that we should be able to have what we want rather than just what we need (after all otherwise I guess we would be back in the caves).
My conclusion is that like many hotly debated topics, there is no right or wrong answer. I believe the best we can do is try to minimise our impact, especially as I find caves to be rather dark and cold at this time of the year...