In short, it looks very much like the Google Candidate cards from the Fox News partnership but expanded to Google local businesses.
You can see it yourself by searching for [a healthy choice spa] or [escape pod comics] and you'll see the carousel shows animated GIFs in them. It may be the first time Google has shown animated GIFs in their search results.
Google told Search Engine Land that it is a test with a "few dozen" local businesses and the content there is custom and not being pulled from any specific place, they said.
I do wonder if this feature will expand and if so, this can be a very interesting avenue for SEOs to go after.
Forum discussion at Google+.