If you still have incandescent lights in your house or business, here is some good info from energy.gov website giving you good enough reason to replace the old incandescents with CFLs or LEDs.
The key results of this analysis indicate that the average life-cycle energy consumption of LED lamps and CFLs are similar, at approximately 3,900 MJ per functional unit (20 million lumenhours). This is about one quarter of the incandescent lamp energy consumption—15,100 MJ per functional unit
ENERGY SAVING INCANDESCENTS -- about 25% energy savings
CFLS -- about 75% energy savings
LEDS -- about 75%–80% energy savings