Following up on this, I wondered what it'd take to emulate a relatively simple processor with as many normal transistors as your brain has neurons, and when we should get to that assuming Moore's Law hold. Also assuming that the number of transistors needed to emulate something is a simple linear function of the number of transistors in the thing you're emulating. This seems like it should give a relatively conservative lower bound, but is obviously still just a napkin calculation. The result is about 48 years, and the math is:

Where all numbers are taken from Wikipedia, and the random 2 in the second equation is the Moore's law years per doubling constant.

I'm not sure what to make of this number, but it is an interesting anchor for other estimates. That said, this whole style of problem is probably much easier in an FPGA or similar, which gives completely different estimates.

I wonder if people would sign up to be simulated with 95% accuracy. That'd would raise some questions about consciousness and identity. I guess you can't really emulate anything with 100% accuracy. The question of how accurate the simulations would have to be before people think they are safe enough to be uploaded sounds like an interesting topic for debate.