Comcast Xfinity customers with X1 set-top boxes can now stream Amazon Prime Video directly through your cable boxes. This partnership was announced a few months ago and is now starting to roll out to customers. This marks the first time that Prime Video has been available through a traditional cable television platform. This is especially significant because it means that Comcast Xfinity subscribers can now choose to get premium channels, such as HBO, Showtime, and Starz, through Amazon Prime Video Channels instead of through Comcast.