"they give me the creeps."

Haven't you, with that statement, accurately reflected your irrational bias regarding the topic of life extension? Presumably someone might have said the same thing back before refigeration and clean water: "you're going to nearly double human life expectancy? Right, get away from me, you creep."

You are of course welcome to your opinion, but such dismissals detract from genuine analysis of the topic and the best avenues for research. And you're wrong about the science being muddy. We have proven, through the very technologies you mention, that it is possible to drastically increase human lifespan. For most of human prehistory and history, setpugenarians and octogenarians were exceedingly rare.

What, exactly, is it that gives you the creeps about people who propose to do the same thing with emerging technologies? I think more likely what is happening is that the idea itself conflicts with assumptions you cling to about the world and your place in it, and rather than attack those assumptions you prefer to deny out-of-hand any evidence that contradicts certain of those assumptions.

Historically, it seems to me, the technologies we've developed that have extended our lifespans are the same technologies that have made our un-extended lifespans more pleasant. I see no reason why this won't continue. The methuselah crowd are basically proposing to find ways to cure disease. Why, exactly, do you find this creepy? Perhaps it seems rooted in self-interest. But all invention is rooted in self-interest. Self-interest and benevolence are not inherently mutually exclusive.

I see plenty of methuselah-skeptics out there, and I consider myself agnostic regarding the predictions of Kurzweil and others on this topic. But I never see the skeptics providing any DATA to contradict the bountiful evidence at the heart of Kurzweil's claims: that information technologies increase in capacity and capability, and decrease in cost, in an exponential fashion. This is clearly evidenced in Moore's law and in the gobs of charts that Kurzweil never leaves home without.

There is nothing particularly shocking in the notion that computers will continue to grow more powerful in an exponential fashion as they have, demonstrably, since their invention. So, even just taking this one technology into account, it is not a great leap to say that the computing power of an iPhone will in 25 years be contained in a package the size of a blood cell, and that will have a profound impact on our medical abilities. We have already created propulsion and other robotic systems at nanoscale, so it is not a great leap of faith to think that these techniques will be rapidly refined and improved over the next decade or two.

It is equally clear that our understanding of the megabytes of data that make up the DNA blueprint of our cells is growing rapidly - exponentially - as the amount of such data begins to soar (thus allowing for exponential gains in analysis). We are rapidly gaining understanding of the properties of these cells (helped a great deal by our exponentially growing ability to see very very small things in real time, and to simulate them to a finer and finer degree).

And yet you dismiss all this as unimportant, and worse, hubristic.

I would rather see the methuselah critics actually put in something close to the thought and effort that the proponents have, as that's the only way there will be an informed debate. Kurzweil and others like him are no doubt wrong about some things, but reactions like yours shed no light on what they might be.

"Steering clear" of uncomfortable ideas is a recipe for getting locked into wrong ideas.