Raising this per suggestion from @dbaron in #59. I'm not really sure how to split this up since as per https://github.com/w3c/webcomponents/blob/gh-pages/README.md the situation is complicated.

• Shadow DOM: we're implementing "v1" and this is now part of the DOM and HTML standards. (Some parts ended up in CSS, UI Events, Touch Events.)
• Custom elements: we're implementing "v1" and this is now part of the DOM and HTML standards.
• HTML Templates: shipped and now part of the HTML standard.
• CSS changes: I'm not sure what the status is here.
• HTML Imports: this is now abandoned I think. We've opposed this in the past: https://hacks.mozilla.org/2014/12/mozilla-and-web-components/.

On top of that there's various new proposals which @smaug---- and I should know more about next week (there's a meeting). My thinking is that we'll open issues for those proposals, but that for the above (apart from the CSS bits) we don't really need anything.