Okay, so, Capaldi. Well, he's great, of course. He's one of the best actors around - I've loved him ever since I saw him as Uncle Rory in The Crow Road. (Yes, I know, most of you don't even know what I'm talking about. I may as well mention, at this point, that I've never seen an episode of Skins or Children of Earth. I've never even seen In The Thick of It, which surprises even me, given that its written by another of my favourite Scotsmen with an Italian surname. I do, however, have Capaldi reading an audiobook of A Song of Stone.) So he's a predictably good Doctor... though it is possible that I'm just perceiving him to be so good because...
A LARGE SECTION OF THE ORIGINAL VERSION OF THIS POST HAS BEEN REMOVED BY THE AUTHOR, PRIOR TO PUBLICATION, FOR REASONS OF POLITENESS
...of course, Capaldi gets plenty of typically groanworthy and arrogant stuff to say and do. His Doctor calls Clara "the asking questions one" and an "egomaniac needy gameplayer", plays that horrific trick on her where he pretends to abandon her (the much-trumpeted 'darkness' of the new Doctor seems to consist of his bouts of callous selfishness being even more egregious, if shorter in length), etc.
But he also gets some good dialogue to play with, and he pounces on it. Some of the mad stuff at the start is well written. It has a genuine edge of mania. The stuff about misunderstanding the concept of the bedroom, and the business with the mirror being furious... this has a really dangerous edge to it, as anyone who has heard genuine delirium will recognise. It isn't 'realistic', but it feels like an indication of real disorientation. It has that funny, disorganised, slightly menacing sound that someone's words have when they're halfway out of a nightmare. And I liked the bit where he interprets the words - or perhaps we should say the feelings - of the lonely dinosaur.
(I liked the dinosaur generally, by the way. I liked that it was played as a victim, a tragic figure, misused and betrayed. Of course, the juxtaposition of the dinosaur with Victorian London has something of that same "I'm mad me!" self-conscious faux-zaniness that creeps into so many Moffat scripts... but it turned out better than that in the end. We didn't even get much in the way of the Doctor being compared to it - the lonely, last survivor, etc - except as a comparatively quiet implication. Based on past excesses, that could've turned far more maudlin and sentimental.)
The best bit is probably the bit with the broom. That felt like something the Doctor would say. I struggle to think of anything Matt Smith was ever given to say that faintly resembles it... so I suppose I should give Moffat credit for changing his style (eventually) to suit a different actor... though I also have to admit the possibility that Smith did get some dialogue that good and I simply don't remember it, or didn't notice it at the time.