There were a couple of things, Avan, that I'd like to note in response to parts of one of your posts.
What is so different from genetically engineering things to engineering nanobots or toasters for that matter? Only the knowledge and equipment required to do each of the tasks.
Actually, there is one substantial difference between the technologies that you have listed, namely, the severity of the consequences that each would be prone to in potential undesirable scenarios. A toaster, in an undesirable case, might catch on fire. A part of the house in question (at the very least, the toaster itself) would burn, and even in the worst of the remotely feasible undesirable cases, the fire from a toaster might burn a section of a town or city before firefighters would be able to stop it.
Contrast this to the undesirable cases of genetic engineering. An unintended result of genetic engineering in an undesirable case might be the disruption of the balance in whatever ecosystem genetically modified creatures were introduced to. For an example of such a phenomenon, consider the
Asian lady beetle (an insect that looks like a tannish ladybug). In Asia, they were a natural part of the ecosystem, and thus existed in a reasonable number. When they were introduced into America to act as a natural predator to a domestic farming pest, they themselves became a nearly innumerable pest to the general population because there existed no natural predator for them in their new habitat. Genetic engineering has an even greater potential to influence ecosystems than the introduction of species to different habitats, but with this greater potential to influence comes the greater potential to influence ineptly. Until the practice of genetic engineering is more perfected, and if the practice of genetic engineering is not always used appropriately, there exists the possibility that scientific "tinkerings" might have a result that is similar in nature to, but more extreme in adverse effect, than that of the introduction of Asian lady beetles to America. Such a consequence, if one were to come to fruition, has the potential be much more detrimental to humankind than even the worst imaginable toaster spawned disaster.
And what's the difference between genetic engineering and artificial selection (breeding) beyond this being a vastly more powerful variant to get the end type of organism desired? Nothing beyond trivial differences by definition, but only dictionary writers would be concerned about those.
The difference between these two things is the process by which each method achieves the same end result (the selection of traits for new generations). Natural selection, though not necessarily "perfect", is effective in the sense that potential new traits for a population are integrated sparsely and consistently over time. If such a trait is desirable (i.e., if it make its owners more likely to survive), then the trait itself will survive to eventually exist in most of the population. If, on the other hand, such a trait is not desirable (makes its owners less likely to survive), then the trait will not spread to as large of a portion of the population, if it spreads at all. This process balances both the needs of the current generation to have a population fit for its present environment and those of future generations to have new traits that might be appropriate for new environments.
Genetic engineering, though, effectively substitutes human expectations of the effectiveness of certain traits for nature's process of trial and error. Even if the potential moral issues of this were to be temporarily overlooked, there still exists the possibility that humankind will inadvertantly manufacure unintended side effects by attempting to create a "magic formula" genetically. Even if this isn't taken to an extent as extreme as Hitler's "blonde hair, blue eyes, German, etc." formula, this would have the potential to cause a practical problem due to the resulting lack of genetic diversity. Even a "formula" as innocent as "not blind, not deaf, no atypical organ development, etc." could be problematic if a trait that was previously seen as "only a defect" turns out to be beneficial in a scenario encountered in the future.
Sickle cell anemia is an example of this; this mutation that results in several negative health effects has the side effect of making the partially afflicted more likely than the general population to survive malaria. If genetic engineering removes all instances of certain "defects", then there exists the possibility that a trait that might have been helpful in a future epidemic is unable to exist because it had previously been eradicated. Such a mistake would not be able to be fixed in time.
To sum things up, I believe that this developing technology is one that is promising and should be pursued, but I believe it should be pursued only if cautiously, given its capacity to be misused. Avan, I realize that this technology plays heavily into your idea of utopia, and I also realize that you consequently desire mankind to have this technology as soon as possible. However, it's also important to remember that the incorrect pursuit of this technology could very well lead to dystopia. You note that the fact that a scenario can be imagined is not proof in of itself that it is feasible or possible, but it is important to nonetheless consider theoretical consequences and, more importantly, the possible ways in which theoretical consequences can develop so that negative potential consequences can be avoided in the future.
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I apologize for the wall of text. I didn't realize that my response was going to be this long.
