On the results page, there’s a button that says Search Tools. Select that, and then under Any Type, you should see an option for Animated. Check it, and when you search, you’ll get GIFs galore that you can preview right there in the results.
We’re not seeing it here on any of our browsers yet, but we’re assuming it’s rolling out slowly. It means you get extra time to consider the appropriate GIF to express your excitement. [Google via CNET]