Eliezer's hard drive analogy convinced me the chances of revival (at least conditionalizing on no existential catastrophe) are good
Why did you find the analogy convincing? It doesn't look like a good analogy:
It's cherry picked: erasing information from hard drives is hard, because they are very stable information storage devices. A powered down hard drive can retain its content for at least decades, probably centuries if the environmental conditions are good. Consider a modern DRAM chip instead: power it down and its content will disappear within seconds. Retention time can be increased to days or perhaps weeks by cooling to cryogenic temperatures before power down, and after the data has become unreadable by normal means, specialized probes and microscopy techniques could in some cases still retrieve it for some time, but ultimately the data will fade. It's unlikely than any future technology will be ever able to recover data from a RAM chip that has been powered down for months, even if cryogenically stored. Of course brains are neither RAM chips nor hard drives, but the point is that having high data remanence is specific to certain technologies and not some general property of all practical information storage systems.
It suggests an Argument from Ignorance: "Pumping someone full of cryoprotectant and gradually lowering their temperature until they can be stored in liquid nitrogen is not a secure way to erase a person." The implicit argument here is that since you can't be sure that cryopreservation destroys a person, you should infer that it doesn't. That's obviously a fallacy.
Furthermore the referenced post introduces spurious motives (signalling) for signing up for cryonics, committing the fallacy of Social Conformance: "Not signing up for cryonics - what does that say? That you've lost hope in the future. That you've lost your will to live. That you've stopped believing that human life, and your own life, is something of value."
Nick Bostrom or Anders Sandberg
Why do you particularly care about their opinion? They are not domain experts, and being futurists/transhumanists there is a non-negligible chance that their opinion on the subject is biased.
I agree with this objection to the hard-drive analogy. Some of the pro-cryonics arguments like the examples of wood frogs, & human drowning victims/coma/flatliners as well as what is currently believed about how memory is stored go some way to showing that memory & personality are closer to hard drives than RAM, but are far from conclusive. I've suggested in the past that would close down this objection would be training some small creature which can be vitrified & revived successfully, and verifying that its memories are still there, but as far as I know, this has never been done.
In June 2012, Robin Hanson wrote a post promoting plastination as a superior to cryopreservation as an approach to preserving people for later uploading. His post included a paragraph which said:
This left me with the impression that the chances of the average cryopreserved person today of being later revived aren't great, even when you conditionalize on no existential catastrophe. More recently, I did a systematic read-through of the sequences for the first time (about a month 1/2 ago), and Eliezer's post You Only Live Twice convinced me to finally sign up for cryonics for three reasons:
I don't find that terribly encouraging. So now I'm back to being pessimistic about current cryopreservation techniques (though I'm still signing up for cryonics because the cost is low enough even given my current estimate of my chances). But I'd very much be curious to know if anyone knows what, say, Nick Bostrom or Anders Sandberg think about the issue. Anyone?
Edit: I'm aware of estimates given by LessWrong folks in the census of the chances of revival, but I don't know how much of that is people taking things like existential risk into account. There are lots of different ways you could arrive at a ~10% chance of revival overall:
is one way. But:
is a very similar conclusion from very different premises. Gwern has more on this sort of reasoning in Plastination versus cryonics, but I don't know who most of the people he links to are so I'm not sure whether to trust them. He does link to a breakdown of probabilities by Robin, but I don't fully understand the way Robin is breaking the issue down.