One of the most important metrics for successful email campaigns in the click to open rate. Getting messages into the inbox is important, but you still need to get the recipient to open the email and then take action based upon it. The use of useful images has always generated a higher click rate, but now studies are showing that using video triples the click through rate of email campaigns.
Implix recommended that to embed video, include a thumbnail in the email with a clear play button, which invites people to click over to the website to view the video.