Can I make an in-place update to new revisions?

[Fennecat]

I'd like to avoid having to re-enter controller, video, and other settings each time I download. Can I just copy a few files from a temporary folder and avoid having to adjust anything aside from game optimizations?

[Shonumi]

I think you can just copy the Dolphin .exe file if you rename it. I wouldn't try loading save states from different revisions (especially if the revisions are far apart).

[neobrain]

^ this. But keep in mind that you're responsible for any possible breakage that occurs by doing this and no one is going to clean up the mess for you then. And it's going to happen sooner or later.