I loved this episode so much I watched it twice...
This was Russell T Davies at his sheer brilliant best. I love parallel universe/time slip/what if? kind of stories, and one of my favourite things about New Dr Who is the way they've played around with Timey Wimey stuff.
The idea that simply by turning right instead of left Donna not only changed the course of her own life, but that of the world's because she never got to meet the Doctor, so wasn't there to save him from drowning when he defeated the Racnos was fabulous. I also liked the way all the companions and people associated with the Doc kept popping off while trying to sort out all the problems that he would have solved in the alternate reality.
I also really liked the parallel with story from series one when Rose tried to save her dad and couldn't. This time around she was unable to save Donna, who's only means of reverting the fateful decision she made was to throw herself under a truck, thereby causing a traffic jam and making her other self turn left as she was supposed to.
Rose herself was something of a revelation. Maybe it's the fact we've got used to her not being around, but boy had I forgotten how good Billie Piper was. She really is an almost impossible act to follow (though against my initial reservations I think Catherine Tate has been pretty good this series, particularly when they stop her shouting) I know there's been some mocking about her speech impediment, but that aside I loved new tough Rose, and the look of pain in her face when she realised she'd come too late to save the Doctor/and Donna asked if they had had a thing going on was a reminder of the power and pathos she brought to the role. The kids are all clamouring for her to come back now, and I can't say I disagree. Shame Billie Piper is so sodding talented she presumably has lots more fish to fry. But hey if she pitches up occasionally from her parallel universe I don't care.
Am absolutely dying to see how it all pans out next and hope that the series finale doesn't end up feeling as much of an anti climax as last year, but retains the power of The Parting of the Ways (my favourite episode from Series One) and Doomsday (which made no 3 cry for weeks afterwards).
Also wondering what the Darkness is and whether I'm right that the ghosts that the Torchwood team see are in fact coming through the Rift from parallel universes (which was how I thought Rose was coming back). My guess is that she will keep appearing and disappearing but that she and the Doctor will never meet properly - or meet and not be able to touch or some such poignant thing. My money is also now on Donna making some big sacrifice to save the Doctor as she knows how important it is to keep him alive, and that Rose already knows this....
And if I've got that all wrong I don't really care anyway because that means RTD has pulled an unexpected rabbit out of the bag, which is much more fun.
Last year I ended up reading far too many spoilers, so I really really don't want to find out what happens next, if only to replicate that moment on Saturday when Donna repeated the words, BAD WOLF.
I so didn't see that coming.