If humankind survives long enough for upload/immortality to become possible, then the living people of that time, or the recently dead, will do equally or better for the task than long frozen corpses. Yes the technology may quickly develop and be able to upload frozen brains, but it is not required.
I do not agree with calculations linearly summing the worth of immortal beings. My guess is that the return will quickly saturates: once you have a being that is willing and capable to improves itself, no more uploads are required. The immortal being can acquire diversity in other ways, and may create diversity too (you don't need a human body to do that). The amount of redundancy in two humans is incredibly high compared to the possibilities in being-space.
Would it have no cost to me and humankind, I would sign up. But given the resources required, I don't think anyone should do it (in the same way that I don't think anyone should drive a Hummer in a city).
I deem that I have other means of becoming "immortal" that are more efficient (yes, including "having kids and transferring them part of my values/knowledge"). My take is that intelligent people should spend their energy trying to convince the population to minimize existential risks, not to sign up for cryonics.
Would it have no cost to me and humankind, I would sign up. But given the resources required, I don't think anyone should do it (in the same way that I don't think anyone should drive a Hummer in a city).
Would it change your mind if the resource cost per person goes down the more people do it? That is something that is not true of people driving a Hummer -- or burial in a graveyard for that matter.
From Mike Darwn's Chronopause, an essay titled "Would You Like Another Plate of This?", discussing people's attitudes to life:
Conclusion, graphs, and references in article. As usual, I recommend reading Chronopause.com as Darwin has many good articles; to quickly link a few: