Well, that was practically perfect in every way. Evil Giles! The reunion of the doctor and Sarah Jane (and the fantastic moment when she discovered the Tardis)! K-9!!!!! How I loved K-9 when I was a very small child, and how wonderful it was to see him again. And his heroic stand at the end made me both cry ("Good dog." "Affirmative!") and cheer ("Bad dog..." "Affirmative!"). Sarah Jane and Rose's antagonism was convincing, but just when I started to get annoyed at this competing-female stereotype, they pulled away from it. It was great to see Micky, who was very funny in this episode ("I'm the tin dog!"). And I loved geeky little Kenny saving the day with his knowledge of bats, and getting cheered by his schoolmates. Oh, the whole thing was a delight from beginning to end. To be honest, I'm still a bit teary and red-eyed - but then, so was Patsington, so I wasn't alone in my sappiness.
The short version for those who don't want to click on the cut: I absolutely and utterly loved it. Sniff.