If the average house changes all bulbs to CF....they will save about $50/year on energy......
Problem is it will cost you about $250 to change all your bulbs...and eliminate all dimmers....because CF' do not work on dimmers...unless you buy the real expensive CF's.
Now if you change to LED's and they are available for all types of fixtures..again problem of dimmers.....but you could have every light on in your house and it would use no more elctricity that a 60W bulb......
Now yes the initial cost of LED bulbs are very high..give it time they will drop....but the best is...you buy one LED bulb it will last 100,000 hrs...compared to about 500 hrs with a CF.....less bulbs to buy lots of money saved and no chemicals to worry about
http://www.superbrightleds.com/MR16_specs.htm