A system is proposed for delivering video content to display devices using a cloud computing model. A plurality of independent physical computer systems cooperate to implement a virtual computer system (“cloud”) which receives media content from sources of media content, and delivers the media content selectively to video display devices. For each of a plurality of users of the virtual computer system, there is a corresponding process (“cloudclone”) running on the virtual computer system which coordinates the delivery of the content to one or more of the video display devices which are associated with the corresponding user. The cloudclone includes respective components for managing the transfer of media content to each of the video display devices associated with the user. This makes possible a straightforward way of migrating video sessions between the devices associated with the user, by changing the corresponding cloudclone. The cloud can also access pre-determined social relationships between the users, and use the actions of a first of the users, to control content delivered to the other user(s) with which the first user has a social relationship.