Expect a deluge of bloggage shortly.
For now I'd like to say Human Nature was without a doubt the best Tennant-story yet for me. From the sketchings of all 10 incarnations of the doctor, the cricket ball, the epic and yet non-violent ways of dealing with the evil-doers and the fact for once the historical period was not white-washed BBC PC-land really worked for me. Finally someone was rather rottenly racist to Martha who gave as good as she got (albeit when said pompous schoolboy had exited scene-left).
I still have a hard time envisioning the original 7th Doctor novel, with Sylvester McCoy playing tongue-hockey to the Jessica Hynes character. McCoy's doctor was not a lady's doctor thankfully. Nonetheless this romance worked far more than the one in the Girl in the Fireplace. Mind you in my book a courtesan is a courtesan, not some glamorous role model.
Overall this season has been an improvement on the last. It's more science-fiction than soap this year. Martha's family (especially her mother) seem more integral to the plot than Jackie, pizza, chips and her quest to grab a bloke ever were. And they're far less irritating - the mother's fear and loathing of the Doctor are pretty understandable. Doubtless they're going to pull out the footage of the Doctor killing a pretty similar looking girl to Martha at some point - according to Martha's myspace account her mother was pretty upset when the cousin died in Doomsday.
This season the Doctor has seemed more vulnerable and the various challenges have taken him to the edge. In short, he's scared, which is good. In Season 2 he and Rose swanned about various places, wise-cracking while people were savaged by werewolves and like, seemingly unphased by anything (except possibly in the Impossible Planet but that contained the cringe-worthy bit at the start where they burst out laughing at the possibility of immediately fleeing in the Tardis) and always getting off scott-free. Let's be honest, Doomsday wasn't really a suitable payback for their cockiness.