In short, LED bulbs are still to expensive. Nickel pointed to one bulb for sale on Amazon with a cost of $32.99 (+6.99 shipping). It claims to last 50 times as long as conventional lighting. I found another bulb for under $19 (+2.5 ship). That one has a lifetime guarantee. Whether they cost $20, $30 or $40 thats still too expensive.
A typical CFL (Compact Fluorescent Lamp) can be bought for around $1-2 nowadays. The CFLs last around 5-10 years.
You could buy a 10 pack of CFL's for $10 or $20 and they would last you 50-100 years total. On a cost per year basis the CFL is still cheaper than the LED even though the LEDs last several decades.
Theres another good reason to delay on buying a LED. In the future the cost of LEDs is likely to drop further. As the technology matures and they become more commonly used the prices will drop. Its quite likely that in a few years LED prices will be well under $10 and may approach the cost of CFL's today.
LEDs may be a great technology but right now they simply cost too much.
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