Google launched this morning at the AMP Conference something they are calling AMP Stories. They are swipeable user interfaces that tell you a story. Google describes them as a "mobile-focused format for delivering news and information as visually rich, tap-through stories."
Here is a video demo of them:
Google launched them with these partners so far; CNN, Conde Nast, Hearst, Mashable, Meredith, Mic, Vox Media, and The Washington Post.
Here is a GIF of it in action:
Visual Stories:
This is how they will show up in mobile search, at least for now:
You can see them in search yourself on your mobile phone by going to g.co/ampstories.
There is a feature to ping Google with AMP content but that I am told is not for search but for AMP to refresh your AMP page cache.
FWIW I think the AMP ping only updates the AMP cache, it doesn't force indexing. Anyway, the CMS or its plugins will/should do this for you :)
— John ☆.o(≧▽≦)o.☆ (@JohnMu) February 13, 2018
All the developer docs are available over here. Techmeme has a lot of coverage as well.
Forum discussion at Twitter.