For an alternative view, see this essay by Eric Raymond.
ESY plays Go! Cool! Now I'm super-certain that his Words of Wisdom are the Font of All Knowledge.
Go Eliezer! You rock! Keep doing what you're doing, as it's very interesting and very fun to read!
Actually, maybe you had better tone down the awesomeness of your posts a bit. (Maybe you could do that by not mentioning the Singularity so much.) If you don't tone it down, I fear I'm in danger of careening off into a Super Happy Death Spiral based on your awesomely cool ideas.
Ian C.: Is there any reason in particular that you think that adults are so different from children? I would say that most adults most of the time act pretty childish, though they often couch it in a form that seems more mature.
I have to recommend Eliezer's essay on his web site An Intuitive Explanation of Bayesian Reasoning. I am sure that everything on there (yudkowsky.net) is well worth reading, but I haven't gotten to anything else yet.
Great parable, but I don't think things would actually happen like that. If that really happened, a Green would almost certainly see the sky as just as green as a Blue would see it blue. Light underground is probably of substandard quality most of the time, no pigments underground exactly match the color of the sky, there have been experiments that have shown that native speakers of different languages will classify the same color as closer to different colors based on their native language. The Greens and the Blues may have the same language but their perception could change if they were raised and lived in their own isolated group.
Finally, there are some human above-ground cultures for which the color of the sky and the color of vegetation are the same word, Hawaiian uliuli for example. So we can just say it's all uliuli and then there's no more possible debate at all anyway.