A few quick things on CFLs for those new to them:
Look for the colour rating and choose one you like. http://en.wikipedia.org/wiki/Color_temperature#Categorizing_different_lighting
Unlike the old incandescent, the new fluorescent bulbs come in different colour spectrums. Get a "warm" colour range if you want that incandescent look. The "cool" colour spectrum provides more of a true white light. We got the cool look first unknowingly and it took some getting used to the colour. Since then we've bought the warm lights and they do emulate incandescent well.
Note that florescent bulbs can take a minute or so to get up to their full lumen level.
Installation is now super easy, even with small sconces (many short fluorescent bulbs being sold). The bulbs are made with the same screw socket ends.
Fluorescent are more expensive and will last a ton longer. In the past five years i've had only ONE F bulb burn out, BUT this one sits in the garage at -30C in the winter (they are only rated down to -15C). In that same time, i've replaced my closet bulb (incandescent) 3 times this past year, and two in the basement stairwell twice (they are all now fluorescent).
Dimming: you can get dimming fluorescent BUT this has to be stated on the label. Otherwise do not use dimmer switches with fluorescent.
Disposal: Many still contain trace amounts of mercury. Most bulbs can be brought back to Home Depot for proper disposal. Don't throw them in the garbage!http://www.popularmechanics.com/home/reviews/news/4215199
I have yet to see any LED socket lights around our location but the idea is interesting in the perspective of saving power and being easier on the environment (no mercury).