I'd say no differently mobile than an ordinary human if maybe a bit slower to account for decay/rigor mortis. Slow shuffling zombies creates too many questions and problems when it comes to the action in a movie. Namely on how something slow moving can be so hard to escape from and overcome?! But I even more hate a modern trend to make zombies movie very, very rapidly almost having super-human levels of speed, strength and agility which makes even LESS sense.
Slow-moving monsters (i.e. the Frankenstein monster) keeping up with fleeing victims is a trope of Horror fiction. It doesn't need to make sense-- it's artistic license. It plays on the emotions. No matter how far or fast you run, it's going to get you. But it's going to take a while, so you have plenty of time to be terrified.
There were NO zombies in 28 Days/Weeks later. They were Rage victims, they did not die. In fact you see Rage victims dying of starvation and exposure. I have no preference for walkers or runners, but i really hope they dont screw up World War Z. I love that book so much and am disappointented the film has deviated from the novel so much. Having said that the trailer does look very good. Fingers crossed.
Spreading an infection by biting is the least efficient method ever (hence why rabies hasn't wiped out the world's population). Having Zombies run makes the chances of it spreading at least more realistic. However, if I'm watching a zombie movie, I've already suspended disbelief a significant degree, so I'm indifferent to which version is chosen.
Zombies are people too, you know! Or at least they were people. Or they're still sort-of-people. Hmmm, back to the drawing board on this one.
The primary fear the zombie movies play upon is being eaten alive. To that extent, fast zombies better emulate wild animals, and so amplify the predator/prey instinct in the back of the mind. I'm glad that a majority of you find slow zombies scary and fast zombies silly. While you're busy mocking how silly it is for a reanimated corpse to have normal reflexes after rigor mortis would be dissipating, I can run away and make sure you're the closest source of food.
I never really bought into runners, except for short distances: I have this concept where David Attenborough from a relatively untouched UK travels to the US to feature a nature documentary on zombie ecology. To him zombification is a return to cold-bloodedness like reptiles. His astonishing find is that zombies actually eat less while dead than when alive, and can go longer without eating--making zombies less a strain on the environment than live humans. They go into shark like feeding frenzies, but spend most of their time in a torpor, like basking crocodiles. He then down loads his own conciousness into a jack in the back of his neck (Matrix style) and allows himself to be bitten. He describes what it is like to turn into a zombie, with his genius intact. He speaks out of a radio collar, and is along for the ride now--the zombie in full control of his locomotion, but still has to worry about head shots. Having David on The Walking Dead would be perfect. You would do an episode like MASH where you actually don't see our heros close up--only in the distance. You have them split up, and killed one by one. (wheather they were slated by Comic or script to die or not. That way, if the network pulls the plug early, you insert this story to wrap things up at least. Otherwise it becomes a dream sequence. Now to me the zombie hordes in WWZ are beyond even running zombies. To see how they spill over each other, it is almost like looking at a nuée ardente, a pyroclastic flow charging at you--a powder avalanche. These would be supernatural zombies to do that at speed, although perhaps having them look like ants, bridging gaps with their own bodies, forming living towers and battering rams would be interesting. http://www.themarysue.com/medical-journal-covered-zombies http://io9.com/5988778/this-interactive-painting-can-explain-why-we-are-still-obsessed-with-zombies
I have no problem with the idea that a recently deceased/reanimated zombie could be fast moving. A recently deceased corpse should be more mobile/agile than a long desiccated one. WWZ is interesting in that it suggests, at least in the books, that Zack does not decay. Whatever it is that reanimates the corpse makes the body less desireable as food for the bacteria that would otherwise consume us after we are dead. Additionally, the "virus" converts most of the body's fluid into some sort of black gel/goo that helps it retain some moisture and keeps things lubricated. Without decay, the only thing that would prevent a zombie from running is a lack of sufficient energy...but we hand wave over that given that they owuld need the same energy in order to move at all.
Okay, but "sex and bestial savagery" interest me a lot more than plain ol' rigor mortis. And besides, I find giant carnivorous insects, a la The Mist, to be much scarier metaphors of doom, corpses being snacks for creepy-crawlies and all.
Sunday movement? This isn't some other goddamn liberals special interest group seeking rights for a bunch of people who don't deserve them is it? Oh. Nevermind.
The zombies in World War Z do decay, it just takes alot longer. Most of the necrotic bacteria avoid selenum, the virus that reanimates the corpse.
This is why I think The Walking Dead has made a good choice in having the most substantive epidemic being reanimation of the dead. Spreading of infection through bites or what have you is secondary. The recently dead, the newly dead & the dying will add to the plague. People die. It's the one thing all of them do eventually, & that is the only prerequisite for continuing this epidemic. The potential of being bitten just adds another imminent threat to an already fragile existence in which there is no civilization, & life is already a dangerous struggle
Well, that's also part of the traditional method. Zombies were just the reanimated dead. People didn't turn into zombies because they were bitten, people turned into zombies after being bitten because they were dead.
But in normal life it's possible to be bitten and not die. Is it not true that a zombie bite in whatever form - a Romero film, the Zack Synder remake, even in this show - will actually cause death? So a bite of equivalent force from a living human won't kill, but from a zombie, it will. Therefore the bite does cause zombism - eventually.
Why then in the Walking Dead did they cut off Herschel's leg. It's implied but not stated that the bite itself has some kind of aombie infection that can spread.