Via Chris Desrochers on Twitter, Google is now showing a date selector on the Google Knowledge Graph Carousel for some queries that benefit from it.

For example, when you search for hotels in a specific area, it makes sense to be able to change the check-in and check-out date so availability and pricing changes in the carousel.

I assume as time goes on, the carousel will add more and more refinement options for different types of queries.

Forum discussion at Twitter.