So basically a rundown of what is known...
- Moffat will be writing a finale that is at least two parts. He has an apparently brilliant idea for the cliffhanger in the penultimate episode.
- Moffat has hinted that we may yet see another ghost story in the show, presumably in Series 9.
- Mark Gatiss said he had two scripts lined up for Doctor Who. One of these was Robot of Sherwood, the other presumably for Series 9 or later.
- Tom MacRae has hinted on several occasions that he has written another script for the show. It has been suggested it may involve Zygons.
- Neil Gaiman has said that we haven't seen the last of him, and has ideas for the show.
- Jamie Mathieson has said that he pitched four ideas for Doctor Who, one of which got him the writing gig for Series 8 (namely Flatline). Speaking to Den of Geek, he's said he's keeping the other three ideas a closely guarded secret in case they ever become a reality in Doctor Who or indeed another show.
- Neil Cross supposedly wrote another script after his two Series 7 episodes. It remains unknown if this'll be commissioned or not.
- Someone of apparent significance tweeted something along the lines of "13 is better than 12 #DoctorWho" which has led many to suspect that we'll be getting a run of 13 episodes in Series 9, rather than 12 again.