11/22/63/YMMV

Harsher in Hindsight - While telling Jake about the horrific history of alternate!2011, Harry mentions that "four of the Japanese islands are gone" due to the Earth's increasing seismic instability. This may or may not count as a Funny Aneurysm Moment, since most of the book was completed by the time of the 2011 Tohoku earthquake, but the actual quake is later mentioned in the story. Speaking of the Japanese disaster, also worth mentioning is how in the alternate timeline a nuclear meltdown in Vermont irradiates much of New England.
Jerkass Woobie - Oswald is depicted as a somewhat sympathetic character.
Tear Jerker: At the end of the novel, Jake has a choice: Either go back to the present to save all of reality as we know but leave the love of his life and all his new friends in the past, or stay with Sadie in the past to be happy and risk damaging the future again. He chooses the former.
- Sadie's death. It doesn't last, but still.
The Woobie - Harry Dunning. Not only does his essay move Jake to tears (and help inspire his journey), the universe shafts him in all three timelines; in the normal one his dad murders his entire family and cripples him (Harry) for life, in the next one he's killed in Vietnam, and in the final one he's left paraplegic in the war.