I have been somewhat fascinated by the idea of the singularity, but ultimately I guess it seems kind of, I don't know, naive and messianic. So this Bloggingheads episode between a dude who works at the Singularity Institute and a philosopher skeptical about that sort of thing is a good listen for me. It is a fairly philosophically technical discussion, but it's also punchy and good exchange and I recommend it.
The core of philosopher Massimo Pigliucci's skepticism, basically, is that the singularity-heads, for all their quantum theorizing and nanobots and whatever, tend to neglect some of the very brute facts of biology. They have an understanding of a human brain that is fully abstractable, and there's no reason to think that's the way it is.
Early in the dialogue, Pigliucci uses photosynthesis as an analogy. We have a very good understanding of photosynthesis, he says. We know exactly how it works on a cellular level. We can map it out in exquisite detail and put all that information onto a computer hard drive. What all that data can't do, of course, is produce sugar. Why should human consciousness be any different?
Pro-singularity guy Eliezer Yudkowsky's view throughout the dialogue is, basically, no, it is just a matter of getting the data and that is it.
Here's a particular point in the discussion where it comes down to this nub. They're talking about the possibility of uploading human consciousness, and whether if you did this and then left your old body behind, you'd be guilty of murdering your former self:
Yeah, that does not sound right to me, either.