The way I wrote my reply was misleading, sorry. I'm not talking about the specific numbers, I'm talking about the model itself. Remember that even in MWI, for any freak incident that allows you to avoid some disaster, there are zillions of far likelier ways of avoiding that disaster. Consider the following:
While that scenario could happen, it's far more likely that:
Going back to your 'narrowly-avoiding destruction of house' scenario, it's not likely that it will occur due to some freak occurence. It's more likely that it will occur due to some mundane occurence. You'll be out of the house buying groceries. Only half your house will be destroyed. Etc. And even if it does happen due to some freak occurrence, it will only probably be a singular event in your lifetime, giving you no meaningful way to update your beliefs.
To phrase it another way, MWI doesn't make the improbable probable. It can't. Otherwise we'd be seeing freak occurrences happen to us all the time. As Elezier said, it all adds up to normality. Even if Everett immortality is correct and you wind up living for a million years, you'll look back at your life and realize that the path to your immortality was... pretty mundane, probably. You were frozen upon death and revived 100 years later into the nanotech revolution. Your consciousness merged with a computer. Etc. All stuff that we consider relatively likely here on LessWrong.
And my intuition tells me that if you actually construct a simple model this is precisely what you will find. That the probability of P(x | M), where x is the path to your immortality, and M is MWI being true, will be the same as P(x | ~M), preventing you from making any updates to your belief. I haven't actually constructed a rigorous model here and I'd love to be proven wrong, but it's what my intuition tells me.
I haven't been able to find the source of the idea, but I've recently been reminded of:
This is, of course, based on the Multiple Worlds Interpretation: if the lottery has one-in-a-million odds, then for every million timelines in which you buy a lottery ticket, in one timeline you'll win it. There's a certain amount of friction - it's not a perfect wealth transfer - based on the lottery's odds. But, looked at from this perspective, the question of "should I buy a lottery ticket?" seems like it might be slightly more complicated than "it's a tax on idiots".
But I'm reminded of my current .sig: "Then again, I could be wrong." And even if this is, in fact, a valid viewpoint, it brings up further questions, such as: how can the friction be minimized, and the efficiency of the transfer be maximized? Does deliberately introducing randomness at any point in the process ensure that at least some of your MWI-selves gain a benefit, as opposed to buying a ticket after the numbers have been chosen but before they've been revealed?
How interesting can this idea be made to be?