This has the same issues of defining the 'self' that we already do -- namely that none of the cells in your body are the same as the cells that made you up ten years ago. Maybe we're all imperceptibly becoming someone else all the time...
I picture 'self' as a surfer riding a wave. If you could suddenly and instantaneously replace every molecule in the wave without getting the velocity exactly right, the experience changes. History is altered, a fork of you.
