The BBC did a great job creating a fun episode that drew on many of the plot lines from the revived series, while liberally dusting it with fan service for old coots like myself. As an added bonus, the next Doctor was given a (sort of) cameo, and a new purpose was set before the character of The Doctor. The final shot in the episode, as well as the credits, hit me right in the Fan Feels.
Additionally, there was an unannounced cameo that, for the life of me, I have no idea how they kept secret (but, this is the same team that kept Paul McGann's web-only minisode a secret, so I should not be surprised).
If you are a fan, you have probably already seen it. If you are not a fan, seriously reconsider your life choices.
Doctor Who nerd, signing off.
Todd
(Photo credit BBC America)