These odds depend a great deal on the behavior of cryonicists in the here and now, instead of depending completely on the haphazard. Refer to:
RESPONSIBILITY, PROBABILITY, AND DURABILITY, by Thomas Donaldson http://www.alcor.org/Library/html/probability.html
Specifically Donaldson writes:
A new gambling house sets up in Reno. The owner undertakes to bet with everyone about whether or not he, the owner, will do his laundry tomorrow. Bets are made today and close at 6 PM. (Perhaps gambling houses already operate this way?) Do we, then, expect a rush of clients? The problem with this bet is that he, the owner, has some control over whether or not he does his laundry. Not only are the dice loaded, but he gets to pick, after all bets are laid, which loaded die to use. Computing probabilities only makes sense when the events bet upon are known to be random.
So the cryonicist, Donaldson argues, needs to think more like the owner of the casino in this example instead of like a passive gambler.
This odds-based thinking also tends to encourage passivity, a fault which I find in typical "skeptical" evaluations of the idea. The usual skeptic says something like, "Cryonics can't or won't work," period; whereas the skeptic who likes solving problems looks at the situation and thinks more along the lines of, "Hmm, cryonics can't or won't work - if you do it that way." Then he might try to think of ways to improve the statement of the problem so that it looks more solvable.
I read gwern and faul_sname as talking about the odds of convincing a relative to sign up, not the odds of revival.
My paternal grandmother is dying of cancer (not brain cancer). She is still relatively healthy, and is taking chemo, but there is little hope of remission (and even if that does happen, she'll probably die of heart failure fairly soon). Her current plan is to be cremated and have the ashes buried in a graveyard (in my opinion, the worst of both of the "standard" approaches, but that's not the point of this post).
I would prefer if she were cryopreserved, but am unsure how to even begin to broach the subject. I also have no idea how to convince her. She is not particularly religious, but is concerned with leaving as much money for my grandfather (and later my parents and me) as possible. I have previously discussed cryonics with my parents; my father brushed off the idea and my mom looked into it but dismissed the idea because the future isn't likely to want her (I find this argument ridiculous on several grounds). This means that I can't count on them to help talk to my grandmother. I may be able to talk to my grandfather first, but this would probably not be much of an asset: he is into several different conspiracy theories (the most recent ones center around the world secretly being controlled by the "elites" who use the U.S. President, U.K. Prime Minister, etc. as figurative puppets), but my grandmother doesn't seem to believe these and probably wouldn't listen much to his talk of cryonics either.
Any suggestions of how to broach the topic or convince her once the topic is broached would be appreciated. I am currently at my grandparents' house, but am leaving less than a day after posting this (most of which will be spent at the local nighttime, and thus asleep). I would prefer not to upset her, both for obvious reasons and because I may not be able to bring myself to bring it up on the day we depart if it will cause us to leave on a bad note.