Here's a possible problem with my analysis:

Suppose Omega or one of its ilk says to you, "Here's a game we can play. I have an infinitely large deck of cards here. Half of them have a star on them, and one-tenth of them have a skull on them. Every time you draw a card with a star, I'll double your utility for the rest of your life. If you draw a card with a skull, I'll kill you."

How many cards do you draw?

I'm pretty sure that someone who believes in many worlds will keep drawing cards until they die. But even if you don't believe in many worlds, I think you do the same thing, unless you are not maximizing expected utility. (Unless chance is quantized so that there is a minimum possible possibility. I don't think that would help much anyway.)

So this whole post may boil down to "maximizing expected utility" not actually being the right thing to do. Also see my earlier, equally unpopular post on why expectation maximization implies average utilitarianism. If you agree that average utilitarianism seems wrong, that's another piece of evidence that maximizing expected utility is wrong.