Doctor Who - Season 6 Episode 6 - The TARDIS arrives in Earth's future at a factory where human doppelgangers, "Gangers," are used as manual labourers. A solar tsunami frees the Gangers, and the original people they are based on must decide whether to accept their counterparts or eliminate them.
Doctor Who - Season 6 Episode 8 - The TARDIS crashlands in Berlin in the 1930s and the Doctor suffers the ultimate betrayal while facing the greatest war criminal of all time.
The many faces of Doctor Who
The 11 actors who have played the lead role in Doctor Who are sometimes divided into two categories by fans: those who play the role as an exaggerated extension of their own personality, and those who entirely fabricate a "Doctorish persona" to inhabit. Ref. Source 2
Apart from the episode that was to have come out around Christmas, from the beginning of the 9th Doctor I have watched every single episode of the show. Sighs, sadly I have not had the opportunity to watch any of the earlier episodes.
On my favorite doctor, I'd have to say without hesitation that would be David Tennant, the 10th Doctor. One of the things that make him truly interesting when it comes to his role as the doctor is how he himself was such a hand.
David Tennant has said that it was because of Doctor Who, and particularly Peter Davison's performance as the Fifth Doctor, that he wanted to be the Doctor. He even got into acting specifically to play the Doctor. Very much a Promoted Fanboy.
Even better Tennant has now married Georgia Moffett, Peter Davison's daughter, who also had a role as the Tenth Doctor's "Daughter" in one episode. More, before the two even met, Georgia's son said that David Tennant was his favorite Doctor and David has now adopted him when he and Georgia married. Meaning Tyler's favorite Doctor is now his father. They're now a whole Promoted Family.
All in all the whole situation is made of awesome, making David Tennant the poster child of the Promoted Fanboy in ways that are beyond imagination.