In my residence, I have used CFL's extensively. The color output has come a long way, and they really put out the light. They also are cool running. The daylight versions are a bit intense for a lot of indoor applications. A big drawback has been their inability to fire at low temps and the low light they put out at first even indoors. They are working on that. I now have some outdoor fixtures with CFL's that are just terrific. They have fired so far at 10 degrees F, and I will test when it gets colder.
I tried LED's at work for an inspection appllication. We use spot lights to inspect for scratches on kitchen cabinet doors before finishing. It is time intensive, and the heat from the spot lights can make them unpleasant to work near. I wanted to try LED's because they are cooler, and the diretional light could be better for highlighting scratches when shown at steep angles to the surface. The light intensity could also make inspection easier. Well, they were $40 each, and really didn't work as well as I had hoped. They are much heavier then the incadescants, which was a problem for the fixtures we use. They did run cooler, but really didn't show the scratches they way I had hoped. Seemed like a good idea! I think the sample will make its way into my barn at home. The LED's seem to light no matter what the temperature.