YouTube started expanding the controls that lets you find, share and comment on favorite parts of a video ' which will now include an "image preview or a series of thumbnails with three new features on the YouTube video player."
Rolling over the coming weeks, whether you're sneaking a peek ahead, scanning backwards, or using a thumbnail to find where you stopped watching a video, you'll soon have three options to instantly look through YouTube videos:
Taking a sneak peek
Just hover your mouse over the seek bar and a thumbnail of that moment will appear, and you can click to start watching from that moment.
Scanning through thumbnails
This one lets you preview multiple frames: Now you can drag the handle along the seek bar to "show a filmstrip of thumbnails of previous and upcoming scenes."
Zooming in on long videos
If you're watching a video that's longer than 90 minutes, you'll now see an added feature that lets you zoom in on the seek bar, one and a half minutes at a time. This second bar that appears gives you more granularity for finding that exact moment you want on a long video. Check out Life in a Day to see how it works.
Google also revealed that "an hour of videos are uploaded to YouTube every second."
For now, they only work in the Flash player. If you want to try them, they're enabled for videos longer than 90 minutes. Here's one of them: