Big Walking bags of meat, not exactly the greatest things at surviving. Give it a couple days.

1, Wild animals would drag them off and tear them to shreds
2. exposed flesh would cause them to dramatically rot in certain temperatures
3. inability to heal would cause minor injuries to greatly effect them
4. lack of mental ability would inevitably cause them to accidental killthemselves
5. the whordes of zombies would be absolutely decimated by military and police forces
6. Need I mention the extremely ineffective way they spread the virus, if the only way to infect is a bite don't expect it to spread fast.

If from one day to the other 90% of the human population would become Zombies I guess within 1 week all Zombies would be dead.

I can kill 9 Zombies in a couple of hours so can everyone else. If people need 6 days to decide to kill the Zombies they will die the next day.

For it to be a challenge the ratio must be 10000 Zombies vs one Human. This will require a daily fight like we see in Walking Dead.

We gotz no guns in australia. So are we fucked? 

Best zombie killing weapon i have is a cricket bat, and if you have played zombiu they are'nt very effective. I can use knives but i rather keep my distance.

got any advice for me, master?

"Zombies", like in Resident Evil? Not that long, although 90-95% of the population would be low-balling it. Id say if were going by movies then 95-98% would be more likely.

Whos to say it wouldnt also infect animals? A virus like this may not necessarily be unique to humanity. Things that feed on infected like birds, cats, dogs, rats could all be infected. In Africa, whos to say Lions, Hyenas, Cheetahs, Birds, etc. Wouldnt get infected.

A pretty big thing would be how it started. From one infected? Is it airborn? In the water?

Would livestock be infected? Would it be in the rain,thus affecting fruit/veg?

I don't think animals would eat rotten meat unless they're starving. Wouldn't be too hard for Zs to pick them up and take a bite either, seeing as they won't feel the biting and scratching from the kitties.

Runners (28 days, Dawn ot D remake) = until they starve.
Shamblers (TWD, Night ot living dead) = few months maybe. Maybe a couple years until completely eradicated.

Dig a large ditch. Take a rock and attach a loud noisemaking device. Throw rock over ditch. Push a large boulder or burn them with gasoline.

I feel that if the problem is normal zombies, they would die out by 6 months. "Zombies" like in Resident Evil would take longer consider that the "Zombies" are not fully dead. Demonic zombies would eventually overrun us 

Partly depends on many factors.

Some things many of you are forgetting is the virus itself. How is it spread? Is everyone already infected and just waiting on some form of death? Seems like 100% of people would eventually become a zombie. That's guaranteed new members on their side. A few zombies coming at you and its not as much of an issue, 10 or so and you may have an issue if you don't have a gun with a lot of ammo and remain calm.

Have to keep in mind, you won't have a lot, or any, one shot kills. Unless you've been military trained and so forth. This ain't the movies, go out and go to a shooting range if you think you could hit target 100% of time.

So sitting on roof and just plucking them off isn't really an option for nearly anyone.

Then you have the fact that the world just shut down. Very quickly you have no food, water, electricity, heat, cooling, comfort, safety, etc. And its not just zombies, but other living people who will kill you to take your stored food/water/security/weapons and so forth. Then you take someone else's life and bam, they are a new zombie trying to eat you.

Also you can't just assume they'll decay all quick. As they are not just lying around in the ground. They are mobile. so a lot of the decaying insects and whatnot won't be on them. It'll take a good couple months before natural decay will affect their mobility, but you have to remember that in that time n number of others have died and replaced them.

Basically you'd need to have a safe, well stocked, secure place for at least six months. Hoping the hordes of 100's and 1000's of undead don't sniff or see you in that time as you won't be able to kill off a horde of more than say 15 unless you have a small army of well armed and decent shooting people.

I know I'm missing other things here, like exhaustion, emotions of losing whole family and friends, people who simply fall apart and become a serious hindrance on your attempt at survival, and so forth. As well as the biggest issue for the majority of the world... lack of weapons. In US I could break into my neighbors houses and easily find guns and ammo in many of them. All you pansy ass girls in other countries are fucked. 'Merica... fuck yeah!

most zombies stuff now seems to have the zombies live until death (head chopped off) they dont seem to starve or rot away. With how fast they are killed in these shows I dont think there would be alot of zombies after too long. I think in walking dead they have each killed atleast 10 zombies, so if they were at 90% zombie change rate, than they have each done their part already.

28 days.