How many new servers are going to be needed now that https is used for everything and requests can't be cached?
The main thing holding us back there are browsers that go apeshit if you load images via HTTP on an HTTPS page. Requiring JavaScript or other active content to be loaded from the same HTTPS server would be a good thing in many cases. I think currently ANY https server is allowed, which doesn't actually defend against any kind of XSS, so it's pretty meh. Or is there some kind of meta tag etc. that enforces same-origin? (If not, that would be a cool addition. Maybe a list of allowed domains?)