Let there be light!
I have to agree that a greater prevalence of LED lighting options will lead to more use of lighting. The same holds true in heating, where if you offer people an insulation package for their homes (draught proofing, new boiler, cavity wall and loft insulation), then according to some very good studies, in a third of households the heating bills rise. The term the industry use is "comfort taking", and it's a simple fact of human behaviour.
And that illustrates some of the problems in forecasting demand and energy use, and the partial delivery of claimed benefits. In the move from incandescent to CFL bulbs, the "waste" heat was anything but during the six month or so of the UK heating season. Admittedly using electric bulbs is an expensive way of heating your home compared to gas, but the planet-savers didn't factor in the lost benefits of incandescent filaments, that on a fully adjusted basis were probably around 15% of their energy use. And likewise they didn't allow for the poor light output, poor light quality, and often slow start up of CFLs that caused people to buy a bigger nominal replacement CFL, or to have additional lights on. The only real reason that CFLs have become as widespread as they have is the EU tree-hugger's ban on incandescent bulbs, along with the UK Department of Energy & Climate Change forcing energy suppliers to subsidies or hand out hundreds of millions of CFL's
subsidised from levies on your electricity bill.
Even with LEDs the "crap eco light" problem has not been fully addressed, with lots of low grade harsh bluey-white lights on the market, sometimes low output, and often low reliability at the cheap end of the market. For GU10 halogens, there's plenty of good, reasonably priced LED options with output as good as a halogen, but for other fittings there's a lot of variation, and indeed a lot of crap on the market. At present there's few 100W BC incandescent equivalents available - the CFL versions tend to disappoint, and there's no trustworthy 1600 lumen bulbs I can find.
Curiously enough, one of the biggest benefits of LEDs is in street lighting. The overall energy savings if every street light in the land were LED are modest at around 0.3 GW (cf 2GW for a decent size thermal power station), but the quality of the light is far better, the savings on replacing bulbs half as often add up, and the luminaires (the light fittings) are far better designed with less light spill and darker skies.