Interesting to see Yahoo's launched VideoTagGame:
getting humans to tag sections within a video, to see what terms they use to describe it...........
just as Google did with Google Image Labeler. (See link below).
Yahoo's calling it the VideoTagGame, and it's now available publicly through the Yahoo! Sandbox.
At least 3 people are involved watching a video simultaneously.
And adding the tags they think of as they go.

When 2 people select the same tag, they get points.
One imagines Yahoo! are using this to improve the search results within video, so they can serve up segment-level search results rather than whole videos.
(This will obviously be useful with longer-form content like keynote speeches etc).  

The interesting thing to me about it is that:
it points to the use of humans to codify the meaning within videos.
And thereby underscores the value of manual tagging.

http://www.readwriteweb.com/archives/yahoos_new_videotaggame_lets_you_tag_within_videos.php