The Google Search Console added a new section under the Search Appearance section named "Rich Cards." Rich Cards seem to be a section where Google will show you data about your rich snippets, schema, AMP, App Indexing and other ways for you to enhance your search listings in Google.
Here is a screen shot of what I see in that section currently:
Google announced it last night. It is a new form of rich snippets that look more AMP carousel articles. It is currently only for movie and recipe web sites and is only viewable on mobile for English users on Google.com, right now. It will expand in the near future.
The learn more links to this page that talks about various ways to richen up your search results in the Google interface. This is mostly around structured markup but also "App Indexing for your mobile apps, creating mobile-friendly content or using AMP pages, and exploring and choosing the structured data markup."
I suspect we will learn more about this outside of the description in the Google Search Console that reads:
Fix errors in your rich cards or enhance your cards with additional data. Errors or omissions in rich card data can reduce the feature set available to your card, or prevent the card from being processed entirely.
We did not find any structured data for rich cards on your website.
Rich cards are a good way to provide data to Google Search about events, products, or opportunities on your website. Rich card data can be displayed to users in a variety of formats on different devices, and can help drive traffic to your website.
Here is a photo of what the errors may look like in the Google Search Console:
Here is a photo of what the user may see in the search results, compared to not seeing it at all or seeing just rich snippets:
Aaron Bradley also posted something about this on Google+ where he goes over many of the other changes. So take a look there was well. Most of this should be clarified by Google over the next day or so.
For more details, see the blog post.