Rumour
During the ultimate war, a Zygon informed the assembled incarnations of the Doctor, in an attempt to convince them to stand down, that the Nestene Consciousness was rumoured to be "no more" as a result of attacks waged throughout history by time travelling Sontarans. (GAME: "Enter... the Zygons!")
Behind the scenes
In invalid sources
After commending multiple Dapol action figures on how lifelike they were, the Seventh Doctor told Ace that he had heard rumours Gerry Anderson was going to become the new producer of their programme. Meanwhile, Ace produced action figures of both herself and the Doctor, substantiating the rumours she had heard about them being replaced. (NOTVALID: Doctor Who? 153)
Other rumours regarding Doctor Who included the suggestion that Ken Russell was going to direct the show and that Marvel Comics were going to bring the show into the Marvel Superhero Universe. (NOTVALID: Doctor Who? 191)