I think 850 lumens is good for a 60W replacement, but 100W? not so much. Not to mention, 83 lm/W? Psh, please.

Now, you could easily squeeze 900 lumens out of an MC-E with adequate heat sinking, but assuming enough heat sinking and power to do this, the light pattern will be a big issue as well. One approach that seems to work alright is shining the LED into a translucent dome. Perhaps with some modifications, you could use this method without too much loss in output. Perhaps even an acrylic optic to allow for a “fatter” dome that can be seen from a larger angle, could help create a softer, less-directional light.

As for your A19 retrofit that will fit in existing sockets, you very well know that the biggest problem is the removal of heat. My question is, do you think that heat is so much of a concern that in order to make truely acceptable bulbs comparable to the higher-wattage incan.’s, we would need to redesign a better socket that can aid in the removal of heat?

If you are thinking of making a design that fits within the dimensions of a regular bulb, I’m thinking it’s time to go active with the cooling. It would add quite a bit onto the final price, but that new technology developed by Georgia Tech, (trademarked as synjet or something of that nature) seems promising. Don’t know if it is truely silent, but if it were, that would definitely be a plus! basically, a diaphram increases and decreases the pressure in a chamber, and through some sort of fluid dynamics magic, results in a directional jet of air that can be directed over a heatsink.

Anyways, I’ve begun to ramble. Cree, if you’re listening, let me live in your basement!!!