I know we sell fluorescent bulbs and have contracts with a number of institutions and banks to replace bulbs (need to be disposed of properly, which cost money), but never heard of anyone just screwing in an LED bulb to replace a CF or incandescent.
I have a light over the kitchen sink that I leave on a lot, shutting it off when I go to bed.
I swapped out this for the CFL, which was installed when I went from incandescent to CFL.
9 watt LED bulb 
