1. The trailer for Going Postal is online. It's one of Terry Pratchett's best Discworld novels, so I expect it to be good. The adaptations have so far been pretty good. I didn't like the Hogfather book as much as most of the series, but the adaptation was great, and The Colour of Magic adaptation (which included the stories from the book of that name and its followup, The Light Fantastic) was very well done. This is the third by the same people, and it's got an even better story to work with, although the downside of that is that it will be harder to measure up to the book.
2. Terry Pratchett has written a letter updating fans on how he's doing. There's no mention of how he's doing with his Alzheimer's in general (other than the clear implication that it's not easy for him right now), but it sounds as if he's done with the first draft of his next book, which awaits editing and revision, and there's a long diatribe against some of the people writing letters to him.
Some of them seem pretty evil, but it doesn't justify his lumping together those who oppose assisted suicide or abortion with those who wanted to outlaw painkillers during labor because it negates the curse of Genesis 3 or those who opposed letting women vote. I expect better of him than this. I feel sorry for him having to put up with some of the ridiculous mail he's been getting, some of it giving a bad name to things I happen to agree with, but it doesn't justify the association of all who disagree with him on a contentious moral issue with those who held positions in the past that we all disagree with now.
I'm curious about the reference to Chesterton's fame "fool the prophet". Google turns up exactly zero on that phrase with his name. Does anyone happen to know what he's referring to?