http://www.youtube.com/watch?v=TBNDYggyesc#t=24m30s.
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Google Video has a similar way to link within a video: add #XXmYYs to a URL. YouTube implemented another feature from Google Video: when you mention a time value in a comment, YouTube automatically creates a link that takes you to that sequence.
It seems that YouTube gradually adds all the features from Google Video: captions, MP4 downloads (not yet linked from the interface), theater view, but Google Video doesn't receive too much attention. I wonder if Google will disable the video uploading feature from Google Video and migrate all the existing videos to YouTube.
{ via TechCrunch }