Read Snuff, by Terry Pratchett. (And you can kind of tell I moved near a used bookstore. . . and the local public library is quite excellent. . . and moving also was an opportunity to get all the books out of boxes in my garage and onto actual bookshelves. Some of them are even lightly sorted. I've been reading a lot, is what I'm saying.)
Anyway, Snuff. I'm not going to make an overall summation -- it's the 39th discworld book, and you've probably already made up your mind whether or not you like them -- but I did want to observe that this book has one huge stylistic defect that wasn't present in the others. The dialogue's all been replaced with paragraph-long rants, giant hulking stilted monologues. These characters used to have distinct voices, and now they have an uncomfortable tendency to preach in unison.
When I was writing seriously, my co-author and I would stand in the kitchen on weekends and read segments aloud. It was a good way of catching typos, but it was also a good way to get a sense of just how bulky the words were, how unwieldy and dull they became when ingested one-by-one. It's a thing that's easy to miss when you're familiar with your own style, and scarcely have to read one word in five to know the entire sentence.
(As you might guess, the livejournal does not get this treatment.)
Pratchett used to know this, and I suspect he edited quite aggressively to "cut out the bits readers tend to skip". That he didn't -- well, it's in poor taste to leap to the conclusion that Alzheimer's is catching up with him, and it's tragic, and something I don't want to think about myself -- but I'd rather not leave that possibility to lurk in the background, so I may as well say outright: I think, at very least, the difficulty that he now has writing negatively affected the rigor of his hitherto customary editing process.
Other critics have mentioned that they disagree with Pratchett's political philosophy, or with elements of his characterization. I don't know about that, because in some ways I'm just a simple writer. I took offense to a mechanical issue with his writing, and wrote about it at length because apparently I was much more offended than I realized at the time. The rest you can judge for yourself.