Since Divia said, and Eliezer retweeted, that good things might happen if people give their honest, detailed reactions:

My honest, non-detailed reaction is AAAAAAH. In more detail -

1. Yup, this seems right.
2. This is technobabble to me, since I don't actually understand nanomachines, but it makes me rather more optimistic about my death being painless than my most likely theory, which is that a superhuman AI takes over first and has better uses for our atoms later.
3. (If we had unlimited retries - if every time an AGI destroyed all the galaxies we got to go back in time four years and try again - we would in a hundred years figure out which bright ideas actually worked.) My brain immediately starts looking for ways to set up some kind of fast testing for ways to do this in a closed, limited world without letting it know ours exists... which is already answered below, under 10. Yup, doomed.
4. And then we all died.
5. Yup.
6. I imagine it would be theoretically - but not practically - possible to fire off a spaceship accelerating fast enough (that is, with enough lead time) that it could outrun the AI and so escape an Earth about to be eaten by an AI (a pivotal act well short of melting all CPUs that would save at least a part of humanity), but that given that the AI could probably take over the ship just by flashing lights at it, that seems unlikely to actually work in practice.
7. I think the closest thing I get to a "pivotal weak act" would be persuading everyone to halt all AI research with a GPT-5 that can be superhumanly persuasive at writing arguments to persuade humans, but doesn't yet have a model of the world-as-real-and-affecting-it that it could use to realize that it could achieve its goals by taking over the world, but I don't actually expect this would work - that would be a very narrow belt of competence and I'm skeptical it could be achieved.
8. Not qualified to comment.
9. Seems right.
10. Yeah, we're doomed.
11. Doomed.
12. Seems right to me. If the AI never tries a plan because it correctly knows it won't work, this doesn't tell you anything about the AI not trying a plan when it would work.
13. "It's not that we can't roll one twenty, it's that we'll roll a one eventually." I don't think humanity has successfully overcome this genre of problem, and we encounter it a lot. (In practice, our solutions are fail-safe systems, requiring multiple humans to concur to do anything, and removing these problems from people's environments, none of which really work in context.)
14. Doomed.
15. Yup, doomed.
16. I'd also add a lot of "we have lots of experience with bosses trying to make their underlings serve them instead of serving themselves and none of them really work", as more very weak evidence in the same direction.
17. Doomed.
18. Doomed.
19. Not qualified to discuss this.
20. We are really very doomed, aren't we.
21. This seems very logical and probably correct, both about the high-level points Eliezer makes and the history of human alignment with other humans.
22. Seems valid.
23. Not qualified to comment.
24. You know, I'd take something that was imperfectly aligned with my Real Actual Values as long as it gave me enough Space Heroin, if the alternative was death. I'd rather the thing aligned with my Real Actual Values, but if we can't manage that, Space Heroin seems better than nothing. (Also, yup, doomed.)
25. Not qualified to comment.
26. This seems valid but I don't know enough about current AI to comment.
27. Good point!
28. Yup.
29. Yup.
30. Yup.
31. Yup.
32. Good point.
33. Doomed.
34. We do seem doomed, yup.
35. Doomed.
36. Indeed, humans already work this way!
37. This is a good point about social dynamics but does not immediately make me go 'we're all doomed', I think because social dynamics seem potentially contingent.
38. You're the expert and I'm not; I don't know the field well enough to comment.
39. No comment.
40. No comment; this seems plausible but I don't know enough to say.
41. No comment.
42. No comment.
43. No comment.