There should be a

in the thread title, because this is actually really exciting work.
https://www.theglobeandmail.com/news/video/video-russian-scientists-attempt-jurassic-park-like-revival-of-woolly-mammoth/article2400026/Essentially, the plan is to take mammoth DNA preserved from specimens found in permafrost, implant it into an elephant's egg, and then implant said egg into a live female elephant. Sounds simple, but there are some major hurdles:
1. This is the procedure by which we achieve cloning of live organisms, but cloning has some major drawbacks - differentiated tissues (i.e. anything that isn't a stem cell) have non-reversible changes to their DNA and chromosome structure. Organisms cloned from differentiated tissues have all kinds of major health problems. Best fix is to find non-differentiated or only slightly differentiated tissues, which means hoping there's some DNA left in the bones.
2. DNA is tough but not that tough - most of the world's mammoths died out about 10,000 years ago. The cold and permanently stable temperatures of permafrost will have done a great deal to preserve DNA (especially if the corpse partially-dessicated), but it's still going to be a major undertaking to assemble a complete genome.
3. Mammoths and elephants are closely-genetically related, but there's always the possibility that an elephant's immune system could prevent the growth of or kill a mammoth embryo.
4. Behaviour is only partially encoded in DNA. Even if you clone a mammoth, it's still not going to fully know how to actually live like a mammoth. Behaviour evolves much faster than biology. (Here's where I invoke Crichton).
But, notwithstanding the hurdles, this is a crazy-cool project. The applications of addressing the hurdles alone will be enormously beneficial.