Several weeks ago, Google added the ability to preview YouTube videos within its GChat feature. Now, it has taken this function to its logical conclusion: Users can watch YouTube videos directly within Gmail. Nice.
Vishal Kasera, software engineer, writes, "We picked stuff that often shows up in e-mail: YouTube videos, Picasa and Flickr links, and Yelp reviews. Turn on Picasa previews from the Labs tab under Settings, and rather than having to click on a Picasa album link to see the photos it contains, you can see photos right in the message itself." Same goes for YouTube, Flickr, and Yelp.
This means you don't have to open a separate window or tab to watch YouTube videos that people share with you. You don't have to leave your Gmail at all. Very convenient.