Halogen lighting seemed like it was going to offer a good alternative - and it did in terms of light output. However, that intensity created a lot of heat, and one had to be careful where halogen bulbs were used.
In recent years, xenon offered an alternative to fluorescent lighting - especially in kitchen areas such as under cabinet and toe-kick lighting sources. Then came the CFLs - the compact fluorescent lightbulbs.
During this evolution, the lowly incandescent bulb was falling into disuse due to its relative inefficiency - it created a lot of excess heat that was not part of illumination. Finally it was largely banned from production and sale in the US.
Along the way, LED (light emitting diodes) were coming into their own. Once quite expensive and not suitable for use in lamps and other applications, they now are available in a very affordable price point and are offered from night lights to dimmable recessed lighting and spotlights.
I love the more than 20-year suggested lifespan of the LED bulbs compared to just a few weeks with the CFLs and maybe a year or so with the traditional incandescent bulb.
So, now that we have LEDs, they are widely available in a variety of sizes (physical size as well as lumens and color output) and they are cost effective to purchase, what is the issue?
It seems that researchers at MIT have been trying to reinvent the incandescent bulbs and have done so to this point by surrounding the filament in the bulb (the tungsten metal that heats up and glows when electrical energy is passed through it) with a special type of crystalline structure in the bulb glass that allows the interior surface to capture the energy that would normally be lost as heat and retain it. The light output appears unaffected.
So, are we going to be getting our 60w and 100w bulbs back again without worrying about them being so hot and inefficient? We'll see. Meanwhile, the LEDs are providing plenty of light without generating much heat.