Letters to the Editor
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The view from space of visible light is not incandescent.
"Look at a map of the world based on satellite photographs taken at night and you will see that light emissions from the United States, in particular the east coast of the country, are far higher than from anywhere else. Most of this light is still produced by antiquated Edison-style incandescents."
Most of the light visible from space is produced by various HID lamps used in outdoor lighting. High-intensity discharge lamps (sodium, mercury vapor and metal halide) at up to 200 lumens/watt are much more efficient than incandescents at around 20 lumens/watt. Fluorescents are around 45-100 lm/W depending on type. Current white LED prototypes are about the same as low pressure HID at 200 lm/W. In terms of efficiency 200 lm/W is only converting 27% of electricity used into visible light. See the table at en.wikipedia.org/wiki/Lighting_efficiency
It would be hard to say if more total lumens are produced by which technology but incandescents are normally used indoors for small spaces like homes. If you want to light a large area it is simply too expensive to do it with incandescents and has been for some time.