Humor is a strangely subjective thing. I can sit through a whole Pratchett novel or a Wodehouse story without even twitching my mouth. I'm far from thick-headed and can appreciate their storytelling devices and humor techniques, but my reaction to them is almost academic, as the humor does not resonate with me very often. The last time I laughed at a Pratchett novel was when I was imagining Detritus in the freeze.
Some idiosyncratic humor does resonate with me though. The absurdities in some of the Jasper Fforde Thursday Next stories got a reaction out of me when a similar technique employed in Discworld would have failed, as the Fforde stories strike a certain geeky chord that Discworld misses a little bit. Not Pratchett's fault, but I'm simply not sympathetic enough to his world and characters to internalize his humor and let it move me.
To really enjoy humor, the characters or story or situation or something have to have some kind of empathic link to the reader. It's not simply a quality that "good writers have and bad writers don't", it's a highly personal thing.
I've found the snarky comments in the later Dresden Files books (after book 4) quite humorous, though not something I'd turn into a cult worship thing. I also really laughed hard at the audacity and political incorrectness in some of Christopher Moore's books, though the stories I've read from him mellow out a little bit around the climax and ending.
Some people laugh at veiled but biting satire, while others prefer being smacked in the face with an
(cover the children's eyes please) .