Sharing answers to top q's we’re seeing about the thumbnail experiment: – Custom thumbs aren't going away – 99.7% still see the creator's custom thumbnail – A lot of creators use auto-generated thumbnails, this test helps improve them for those using them: https://goo.gl/A7oDmr
My feedback as one of the people seeing only auto-generated thumbs is that YouTube looks ugly with only the auto thumbs and I wish I wasn't part of this