Trivia: Steven Moffat was so busy on different projects, and the shooting of Series 6 was enough of a troubled production, that he only had time to write one draft of this episode, which is what was shot. Not only is it amazing that this episode turned out as well as it did given that there was only a first draft of the script, this also explains some problems people have with the episode's plot - problems that probably would have been removed had there been multiple drafts.
Trivia: Lynda Barron, the actress who plays shop assistant Val, previously appeared twice in the classic series: the singing narrator in "The Gunfighters", and Captain Wrack in "Enlightenment".
Chosen answer: No, no information is avalible for the identity of the entity.
Repo_Man