Here is a screen shot of a new user interface for videos showing up in the mobile search results. Normally you get a carousel of videos, but here you see a large video at the top, with two videos below and the option to show more videos. When you expand the videos by clicking on the arrow down, it shows a whole range of videos below.

Here is a screen shot from Valentin Pletzer on Twitter:

Compare that to a normal video carousel, which is what I see:

When you click to expand more videos, it shows a lot of videos:

Forum discussion at Twitter.