Or as we used to call it: plain old HTML + CSS.

I shouldn't be webdev-snarky about this because I'm actually super-excited. Newspaper and magazine websites are notoriously among the worst in speed, bandwidth-hogging, and truly needless use of JavaScript. This is an open source project that aims to noodge them into getting better, which would make a lot of people's daily lives better.

Yes, this seems like a very sincere effort by Google to save the web:

http://pandawhale.com/post/67925/googles-plan-to-save-the-web

Twitter notoriously has hated on mobile web -- at one point only letting you be a Twitter member if you would download a native app to your smartphone! -- but maybe things are changing:

https://blog.twitter.com/2015/introducing-accelerated-mobile-pages-0

I believe that things are changing because Twitter HAS to change to survive.