We know that YouTube will get +1 button in the future, but in addition to +1 button, Google has added several useful features that should enhance your YouTube user experience.
It can get a bit frustrating when you need to get back to a specific part of a YouTube video, and you haven't memorized the time of that part, but luckily to this latest update, you'll be able to navigate through the video that you're watching with ease. With this update, each time when you hover over the timebar on a YouTube video, you'll see a thumbnail of the video that should assist you with the navigation. In addition to thumbnails, you'll be able to zoom into the timebar, if you are watching a video that is longer than 90 minutes.
These two features are rather useful, and they are available for several YouTube videos, and we hope that all YouTube videos will be updated to support these two new features.
Source:
YouTube player to get new features | Ubergizmo (http://www.ubergizmo.com/2012/03/youtube-player-to-get-new-features/)