Pretty sweet! Would love to see something similar for nginx.

There is some stuff listed at http://wiki.nginx.org/Configuration but it's more laid out in full examples rather than this code block does X

I'm confused as to how this differs from your typical phishing attack?

Google has a pretty good description: https://sites.google.com/site/bughunteruniversity/nonvuln/ph...

I think the biggest problem with this attack is that many don't believe it to be possible. And why should they, given the inconsistent browser behavior.

Not only that, but good luck keeping up with Apple's developments once they start buckling down and updating the language.

We have a long history of doing more than "keeping up" ;)

What are the legalities?

Swift is just a language specification. It cannot be patented or copyright-ed. Anyone is free to make tools around the language specification. Just like there are many compilers for C/C++ on different platforms, we intend to make one for Swift on Linux/Windows.