People should approach this with a grain of salt. The leading Korean scientist, Hwang Woo-suk, was discovered to have fabricated two articles he published in Science in 2004 & 2005[0]. We shouldn't completely disregard the work, but should definitely be more cautious when judging its veracity.
For those not aware. There's a running joke in the skepticism community, that in the next few years we're gonna have baby mammoths flying around in jetpacks [1]. That's because stories of both mammoth cloning and jetpacks in development keep coming back on the media. Every other year we hear about a new exciting research about either of these, but not only they never delivered, we also haven't seen any real evidence that we have the technology for either of them to become a reality in the near future.
Both jetpacks and baby mammoth share a common problem. They're both things we have already theorized as possible. So we do know we can do it, any research on them could be legit. But there are way too many little technical details in the way to actually make them happen. In the case of cloning mammoths, there are just thousands of little things that could go wrong. From your DNA sample not being as good as you thought, or the womb condition of the elephant not being as appropriate for a mammoth as you thought. To the big elephant in the room (sorry) that is, even if you perfect the technique (we didn't), and happen to successfully give birth to a new baby from mammoth DNA. That new baby is actually not a mammoth. But a mammoth-elephant hybrid. That would be like mating a German Shepard with a Poodle, getting a short dog with curly hair, but with a hair color that resembles the Shepard. And saying "here's a German Shepard". Well, not really. If you really want an actual mammoth that is, at least, very close to a mammoth with little elephant DNA in it. You'll need to reclone that new baby with more mammoth DNA. Even if you assume perfect cloning technique and infinite samples of perfect mammoth DNA. Considering the pregnancy time for elephants. It could take centuries to have an actual mammoth.
So yea, it's exciting research, we love to see it, and it's sure something viable that may become true in the future. But don't get too excited just yet. The correct skeptic stance would be to assume they might succeed, but their chances are very slim to at best, move forward some baby steps in technology. But since that's probably not the best stance to get your research funded, we'll keep hearing about exciting new breakthroughs in baby mammoths flying on jetpacks on the media every other year.
On the mammothness of the newborn, maybe whole the cloning idea is created on a wrong basis. We do use a "birth from a similar organisation" technique.
With the correct DNA and correct stem-cells we could replicate a "real clone womb" (Yes I love stem-cells). This kind of "fantasy" could lead us to a closer cloning.
They exist. They're just expensive, dangerous, and require an expert operator.
There are also strong constraints on the altitude and maneuverability (between physical/design constraints and the increasing likelihood that you'll lose control).
For the sake of science and humanity, we need more of these kinds of "crazy" researches. With ethics and academia rules and funding craziness we are holding our-selfs back.
We should be using on-animal harvested human organs for transplants, or we should be using stem-cells for regeneration, wound curing and so many other things in the wild.
Science should be more agile. Like the story of "one sloc change takes 3 days" science nowadays takes too too long.
Smoke signals? 100 years is approximately the amount of time between the telephone and the internet. The telegraph was around for about 50 years before that. Science has done well, but it's not like the twentieth century magically emerged straight from the stone age.
Just to push it back a bit further, revolutionary France and particularly Napoleonic France established a country-wide system of mechanical telegraph stations. They especially wanted it to warn of British naval attacks, but also for any military news.
It worked pretty well, transmitting, for example, a distance of about 200km (125mi) in about 9 minutes. The Brits would sail up and down the coast and fire on stations when they were feeling bored and mischievous.
Interestingly, Hooke (Newton's compatriot) proposed a similar system a couple of hundred years earlier, but the British military chiefs displayed their usual insight and did not take it up.
In case I'm not the only one who wondered: South Korean, not North. I remember maybe 10 - 15 years back there was some kerfuffle about North Korean scientists being outed as experimenting with cloning humans, so this was the first question that came to mind.
For the life of me I can't find the article but years ago I read an article called something like "Our Genes Are Not Us" in Discover or Scientific American magazine. (I searched them without any luck.) Maybe someone else will have better luck finding the article.
The article mentioned that one of the problems with cloning a mammoth is duplicating the envitro environment as this controls the expression(1) of the genes. In other words, it isn't enough to have "the code", you also need the "computer" to run it on.
(1) A butterfly and a catepillar have the same DNA but it is expressed differently.
0: http://en.wikipedia.org/wiki/Hwang_Woo_Suk