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I think one of the only things we can be reasonably certain about is energy. Many or even most of the changes Charlie listed would require changing much of the technology deployed on our planet (except of course those changes that are more or less inevitable, like rising sea levels). Changing any of the hardware in our world on a large scale requires massive amounts of energy, and energy follows rules that don't change at all over a 500 year timescale.

Fusion seems to be inevitable. I can't say I agree with people who say it'll never be competitive with other energy sources. All that has to be done is to solve the engineering hurdles required to make fusion scalable, and perhaps to add the capability to use fusion reactions that make use of a greater variety of elements. (And yes, those are huge challenges, but we're talking 500 years of advanced engineering operating on something that already works in a simple prototype system.) Once that has been achieved, fusion power can outperform >any< other terrestrial energy source (except perhaps fission), as a matter of physics. I imagine the economics of that will fall into place once that massive supply of energy is made potentially accessible, since there will undoubtedly be demand for titanic amounts of cheap and reliable energy.