For the longest time, videos found within Google’s search results contained thumbnail images of a frame within the video. That is how Google has displayed richer search results, ever since the days of Universal Search.
It seems like Google is testing making those video results a bit less rich by removing the video thumbnail image and replacing it with a small, gray, play button followed by the time of the video.
Craig Gilhooly posted a screen shot of the new user interface test on Twitter. Here is a picture:
Here is what it currently looks like to the average searcher: