Next time someone sends you a Youtube or Google video link on the Gmail Chat, you don’t really have to open it in a New tab or a window.
Now you can just click on the Youtube or Google Video link from your chat window and it plays for you right there.
This is how the preview of the video looks on your chat window…
and this is how it plays, when you click on it.
Note that this feature works currently, only with your Gmail chat and not the GTalk client application.
Share and enjoy your videos, instantaneously!
Via Official Gmail Blog