I don't doubt I would like many of these at least somewhat. Terry Pratchett has always seemed to me to be a cross between Xanth and Hitchhiker's Guide and not so appealing years later, but I have liked bits that I have had described to me. The others listed - except maybe that Ukrainian Tractors thing - seem too drenched in irony, or nuance, or something. Yet, seeing that even I don't like the humorous styles I used to love, it may be the age. Some other generation may have to reclaim simple humor.
Does anyone know anything about the others?
Or you could just comment about book-humor in general.