LED lighting now can be purchased for homes and not just commercial uses. See the excellent piece by Jeff Gelles in today's Philadelphia Inquirer at http://www.phillynews.com/
Should you buy LED ?
Environmentally the answer is yes. Reducing energy consumption is a powerful way to avoid using fossil fuels, clean our air, protect our water. The typical home causes twice as much pollution as the family car. Lighting is a significant portion of home energy use.
Economically the answer is perhaps.
Consider these numbers. LED lighting reduces electricity consumption compared to an incandescent light bulb by about 80%. Deployment of LED lighting across the economy would reduce appreciably increases in electricity consumption.
They last 50 times longer than an incandescent light bulb or the rest of your life even if you are quite young.
But, and there is still a but, they cost $37.
Bottom line is that if you have a fixture that is on a great many hours every day, then LED lighting will pay back its up front cost in a reasonable period.