Under the comments box:

"New! Link to interesting parts of the video with times like 1:24:30 or 0:55."

Adding a time in this format results in a link in your comment that gets you to that part of the movie.

can you upload a picture please?

If I understand what Sander is saying, I think this is what he's talking about:

http://blogoscoped.com/archive/2006-07-20-n71.html

It's slightly different. when you leave a comment you can directly reference a part of the Video by putting the time, when someone clicks the time in the video it jumps to that part of it
(example http://video.google.com/videoplay?docid=7954888536294747683)

That's what I meant, sorry for being a bit vague :)

That's interesting, but I can't see normal users really doing that much.

Nice feature. I wonder what is the future of Google Video along YouTube. I hope they will continue as it is – YouTube community, Google Video platform for New Television.

Ah... I get it! That's a pretty sensible feature to have. I wonder if they'll ever let you annotate the videos too. I'm thinking of something like Flickr let you do with photos – i.e. you draw a box around something and add a note... now that would be cool!

Veotag lets you add notes to the videos, but not drawing boxes around them though.
http://veotag.com

You could do that with the Google Captions thingy, but it would be on top of the video by default and you wouldn't be able to do links.