Den of Geek had an interesting article up about Series 8. There are some minor spoilers in here, so please look away if you want everything to be a surprise.
There was some casting news previously, notably that there would be a new ‘companion’ in Danny Pink, a teacher at Coal Hill School. Whether he is a real companion traveling with the Doctor in the tardis remains to be seen. Also joining the cast is a younger girl, who will play his sister, a pupil at the school. Don’t forget Clara was a teacher there as well.
Let me just get my checklist out… Okay, Ian? Check. Barbara? Check. Susan? Check. Older Doctor? Check. It looks like they may be setting things up to mirror the original crew of the tardis. What does this mean for series 8? Are they going to battle cave men and try to start fire? Meet Marco Polo again? Unlikely, but a possible return to that original dynamic is exciting and intriguing!