WOW, if brands can add a video to their Facebook Timeline cover photos, many things are gonna change. I remember the first time I saw animated gif images within Twitter profiles. Scary or innovative?
Tha agency is called Zaraguza and is one of the most awarded Facebook agency! Check their Facebook page here
How it works?
The Facebook page updates (like every minute aprox) by posting a new image into a Facebook album which is sucked into the Cover image automatically, and is refreshed when new people hit the page or click the refresh button F5.