Yes. Annotation for video works in the same way that annotation works for other file types. Just click on the video screen as it plays at the point you want to make a comment. The annotation will be noted on the video's timeline at the bottom by a green vertical bar, and the annotation comment will appear in the Comments panel on the right hand side.
When hovering over each of the individual comments in the Comment panel, the corresponding "push pin" annotation will be highlighted within the video, and alternately, hovering over the "push pin" annotations within the video, will highlight the corresponding comments within the Comments panel.