Yep, with the episode "Smith and Jones", series three of my all-time favourite show, Doctor Who, premiered on the BBC last night (and was immediately bittorrented by us). With a new companion! (Sob... my Rose... she's really gone...) With a hospital on the Moon! With... talking bipedal rhinos? Um... Okay, sure, what the hell? Why not? A few random thoughts (and be warned, this'll be spoilery):
The Judoon. Possibly just a leeeetle close to the Sontarans. Fortunately, their motivations are plenty different. The Sontarans are all about combat and conquest. The Judoon are about enforcing rather extreme laws and sheer bloody-mindedness.
The Doctor. Well, he's the Doctor, isn't he? Gotta love this look:
Ontological paradox alert!
The Doctor appears to Martha early in the episode, takes off his tie and says, "Like so? See?" Martha tells the Doctor about this later on. The Doctor travels back through time to prove he can do so and takes off his tie in front of her. So... where did the tie-removal idea come from? The Doctor took of his tie because, well, because he took off his tie. It's Bad Wolf all over again!
All in all, a very good episode to introduce a companion in.