Doctor Who: The Girl in the Fireplace: This was one of the best Doctor Who episodes I've ever seen; seriously, I'm putting it up there with Ghost Light on the all-time favourites list. I haven't seen anyone know the Doctor like Madame de Pompadour did, and yet it worked, incredibly well.
The clockwork horrors were like something out of a nightmare - making their entrance from under the bed so appropriate - and yet they managed to evoke pity at their end; well, in me, anyway: my wife - who, I'm happy to say, is enjoying Doctor Who for the first time in her life - found them utterly terrifying throughout, I suspect. :-)
Tennant was absolutely brilliant again; when Louis XV was the only person there to greet him on his final trip through the fireplace, you knew how the Doctor felt just by looking at his face. The writer's use of silence in this new series shows a subtlety I'm not used to seeing; it's really a talent showcase all-round now.
And Tennant's range of emotion was positively manic! So appropriate for a being of his age, I feel. Initially, I'd planned to compare the Doctor's roller-coaster of child-like joy to utter, but sadly, expected disappointment with Eccleston's moment with the tree-woman, Jabe, in The End of the World. On second thought, however, I think any one of Colin Baker's excellent performances would hit just as close to the mark. You just don't expect it from the inconspicuously-dressed Tennant. ;-)