Google rolled out a few updates to your YouTube homepage feed yesterday, including larger thumbnails and a menu to control what content appears in your feed.
Regarding the thumbnails, these also now reel in more information related to the video. For example, if an uploader has commented, posted, or added a video to a playlist, this information is displayed above the image next to their username:
To the top right of each video suggestions on your homepage, you’ll now see a little arrow that includes a menu to let you Hide this activity, Only show uploads from that particular user, or unsubscribe from that user altogether:
Additionally, if you’ve already watched a video, the thumbnail will now be marked as such, so you know to skip it (if you don’t want to watch it again).