I've been having this issue for almost 3 days now where sometimes youtube thumbnails doesn't show up. I've cleared my browser cache and cookies etc but still no luck. Sometimes they appear, sometimes they don't. I'm not having any issues with my internet at the moment so I don't know what's up. Anyone else experience this lately?
Edit: And of course, when I load youtube to take a screenshot and show you, every thumbnail is there -.-
I feel your pain... YouTube has been having issues all week look at @teamyoutube on twitter tons of people are flooding them with reports.