These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
An early chapter features a Palestinian fleeing to Israel for protection. He eventually comes to the view that the zombies are the common enemy, but not before making several references to the Gaza Strip and the belief that Israel would use Palestinians as human shields. Fast forward to the bombing on the Gaza Strip and Hamas using Palestinians as human shields in 2014.
One of the diseases that Breckinridge Scott mentions as a typical "scare" in the US is ebola.
Barack Obama is implied to be the "first choice" for Vice President of the bipartisan war-time U.S. government, but is passed over in favor of Howard Dean. Two years later in the real world, Obama is elected President of the United States.
Minor and slightly debatable example in the book's description of Cuba. Fidel Castro clung onto power throughout WWZ and only submitted when social reforms turned Cuba into a post-war Iceland, economically speaking. Of course, he calmly relinquished his position to his brother temporarily the same year the book was released, and permanently two years after that.
Admittedly, Castro was never "forced from power", he eventually just retired due to declining health in his old age, and the government he started smoothly transitioned to his brother. So he'd still have stayed in power, though Brooks couldn't predict his health...
The soccer mom makes reference to her daughter being a fan of Jamie Lynn Spears, wearing soccer cleats with her brand on them. Just one year after the book came out, Spears' career was destroyed by her teen pregnancyscandal.
Paul Sorvino as Fernando Oliviera in the audio book, discussing organ transplants from infected donors.
Magnificent Bastard: Fidel Castro, even more so than in real life. When it was clear his country was turning against him, he gave up his position and endorsed the new institution, essentially becoming the father of the new government, and a national hero.
Memetic Mutation: Mark Hamill's clipped delivery of "Die, motherfucker, die!" in the audiobook.
Moral Event Horizon: Just what Breckenridge Scott did by tricking the people into buying Phalanx.
Paranoia Fuel: The entire premise of a zombie apocalypse and the all-too-realistic depictions of our governments failing to handle it is enough to keep you awake for a very long time.
In-universe and out example: The possibility of a zombie shambling around that somehow slipped through the cracks of operations like the Battle of Hope or the large scale urban cleanups. The above-mentioned catacombs of France? How likely is it that there are still a few zombies shambling around in there? Or in a dense forest somewhere? And what's to stop it from making it into a populated area at the worst possible place and time.
Or, if you live in a coastal area, a massive horde of zombies can just come shambling out of the water at any time, which is likely considering there are millions of zombies wandering the ocean floor.
I believe the book mentioned that nets are used to cordon off beaches, and now people know how to respond to a large-scale zombie attack. Some people even have homes on tall stilts that can only be accessed via ladder in the event that another Z War breaks out.
Squick: A lot. Particularly the descriptions of "digested" human remains found inside the zombies. And the infection-by-organ-transplant vignette.
Angst? What Angst?: Tommy doesn't seemed to be upset at all when his parents became infected.
Broken Base: The first preview of the movie seems to have divided opinions rather sharply due to the questionable cgi on the hordes of zombies, the fact the zombies are "Runners", the fact that a combination of both questionable cgi and running zombies leads to rather unrealistic scenes of zombies falling over each other en masse as they charge at people, let alone the fact the movie seems to be changing the story of the books even more than previously thought.
The main fans are having issues with the "runners" as the books specifically debunk that theory, the fact that the trailer's making it look like "Brad Pitt saves the world" instead of numerous people who did important things in the interviews.
Narm/Narm Charm: Some people found the literal waves of fast zombies climbing on top of one another to be very dramatic and scary, others thought that it just looked silly.
The behavior of the zombies either comes across as creepy (as it is the case for most of the film) or laughably over-the-top (as it is for certain parts near the end of the film).
The latter involves with the teeth chattering zombie near the end. When Gerry manages to successfully become ill to fool the zombies into believing he's terminal, the thing walks in... and makes the most awkward, dumb-looking, mole-rat looking teeth click for the longest time.
Then there the zombies who instead of moaning or snarling, they squawk like birds.
Not to mention the zombie kept in custody that has bulgy eyes and keeps banging its head on the glass wall it's trapped behind.
There's a scene where Gerry and co make it to their getaway plane on bikes. In-universe this makes sense, because it makes a lot less noise than walking in the rain would and it doesn't set off the zombies. Doesn't make it any less silly, though.
One of Gerry's daughters screaming, of all things, "I want my blanket!" as her father drives through the hole left behind from a garbage truck smashing through gridlock at 30 miles per hour and a horde of zombies is descending from behind them. Yes, she's probably in shock, but it's still...odd.
The Scrappy: Gerry's family, for some. The wife nearly gets Gerry killed by calling his satellite phone (causing all the zombies in the area to activate and attack), the youngest daughter screams every line she has, and the older daughter is basically The Load.
Squick: In the books, North Korea's fate is kept ambiguous. In the film, they manage to avoid a large-scale outbreak by pulling out literally everyone's teeth. That way, if someone's infected, it's almost impossible for them to bite someone and transmit the disease. It's unmentioned whether the higher-ups were exempt.
They Changed It, Now It Sucks: Fans were quick to call it an In Name Only adaptation. This seems to have calmed down with the release of the film, establishing it more as a sidestory in the same universe than an adaptation.
In particular, the zombies in the film work on a fundamentally different level than the ones in the books, completely changing the course of the story.
Uncanny Valley: Zombies don't blink. Not only is this creepy, it also means the surface of their eyes is never lubricated, leading to the eyes becoming scratched and opaque. Hence the traditional white eyes.
Visual Effects of Awesome: A prime example of story dictating visual effects, rather than CGI for the sake of CGI. Everything is practical until it's impossible to depict without FX.
Given that Dr Fassbach is a highly regarded virologist and one of the people the military are looking to figure out the cause of the outbreak, you have to question the sanity of whoever decided to send him into the field with zero combat training, rather than let other, more expendable personnel gather evidence and samples for him. Naturally, only a few minutes into the mission, he panics at the sight of the zombies, slips on the ramp as he attempts to retreat and blows his own brains out when his gun accidentally discharges.
At the Jerusalem wall, everything goes to hell when the zombies hear the refugees singing. They only hear it because a civilian takes a microphone, and simply says "it's okay" to the soldier, who lets her sing. this is unacceptable behavior at any installation (they wouldn't let a random person take over the PA system at a Wal-Mart, let alone a secure military zone), but the Israelis know the zombies are attracted to sound.