8. He Is The Actual "Time War" Doctor (or Doctor 9)
The show has not yet shown the Time War between the Time Lords and the Daleks. There have been hints and mentions and looks of sadness, etc. I always assumed that the war happened during Eccelston's regeneration, but it could equally have happened during the adventures we didn't see with McGann's Doctor 8. I read a rumour before the finale aired that John Hurt was a "part of the Doctor" that existed between what we recognize as 8 and 9. He is a "hidden' Doctor that was kept out of the numbering process for some reason. This could put him during the Time War. This also of course screws up the numbering and makes Eccleston actually Doctor 10, Tennant Doctor 11 and Smith Doctor 12. I don't know if it's just me... but this is annoying and confusing. Likelihood? This is my bet. Even if it screws up the numbering and annoys me, I get chills with the thought of actually seeing some of the great Time War. This also could potentially allow us to finally get a proper regeneration sequence of Doctor 8 (McGann) to Doctor 9 (Hurt) and then on to Doctor 10 (Eccleston). Check out his outfit in this set pic as well. His wardrobe sure looks like an amalgam of McGann's and Eccleston's clothes. Unless of course this outfit was just a red herring to lead all of us speculators down the wrong path...