Youtube added a new feature called annotations, that lets you to add interactive commentary. What it means is you can spice up your videos with cool speech bubbles, links to related videos, channels and search results of youtube content. Users will have full control over the annotations, where they appear on the video and when they appear.
If users who doesn’t want distractions in the form of these annotations can turn it off from the player menu.
Related: Overstream supports more site to add comments and subtitles

See a live example of the video here. Via Google OS
