Google announced they are adding carousel based search results at the snippet level. So if you search for something and Google feels more content from that source is warranted, instead of showing more search results listed below, it will show a carousel box below that you can slide through.
Here is an animated GIF of how it works when you are on your mobile device:
I believe this should be called the snippet carousel.
Google said, "When you search for a topic, just scroll down to see a "carousel" of recent articles, videos or more on that subject. Tap any link to read or watch exactly what you’re interested in."
How do you get your site to show this snippet carousel? Google added some tips on Google+ saying that you can add Articles rich snippets to "help" their "algorithm select the proper images or titles for your carousel results."
Google did add that it doesn't give you a better shot of showing up in the carousel but if you do qualify, it helps them figure out which images to add. Google said:
Note that this markup is purely advisory - Our system use a variety of signals to determine which content to display in SERPs. Just like with Rich Snippets, we do not guarantee showing content you marked up.
Forum discussion at Google+.
