With the passing of the incandescent bulb, CFL's and LEDs are now really the alternative. Is it worth it to run out and replace all your light bulbs with LEDs currently? Obviously the first variable is to look at the cost. LED's are still at the rather high end of the spectrum, with most LED's that fit standard sockets still around $7 to $11 a piece. A rather large increase in price from the ole incandescent, and more expensive than CFL's by about 50%.
Lumen, or light output is the second variable to consider. For years, LED's lacked the light output of other technology; however recent advances in technology makes them a more attractive alternative. Energy.gov uses the term efficacy to rate light bulbs, or lumen/watt. This is a ratio that explains how bright the light bulb is, versus the watts consumed. Current top of the line LEDs produce around 800 lumen for around 12 Watts, which is a comparison to a 60W incandescent lumen output. It should be noted that efficacy does not take into account color or temperature.
Lifetime is an area where LEDs currently shine. According to energy.gov LEDs have almost double the life of current CFL and incandescent bulbs. This allows a bit more leeway in the price, as they will last up to three times as long.
Finally their power quality stamp is the last thing to discuss. If considering for a business, or somewhere that is penalized on power factor, consider this. LEDs have a very poor power factor, unless they have power factor correction built into them. Also, due to the way they are designed, using a lighting control system that dim lights by restricting voltage to the lights does not interact with LEDs very well. As the LED voltage falls below 120, it does dim; however the power factor becomes increasingly worse.
My recommendation is before purchasing them for the home, evaluate your home and your budget before purchasing. It my be more efficient in the long run to install track lighting with LEDs rather then purchasing in socket LED replacements. Listed below are some sources to help make the decision a bit easier to make.