It's difficult to say. It's difficult to gauge how crazy the leadership actually is. Though, conventional wisdom dictates that so long as their standing in the national stage stays the same, they probably won't do anything different from what they've been doing for decades.

On the other hand, North Korea is in a rather unique position with their own brand of crazy stuff that they do. Also, the leadership seems to be pretty horrible in general, and they might just do it to spite the world.

nerd4life123 : I don't think war is what anyone wants. If North Korea starts the war and opens fire there will be huge consequences to these actions which will prompt the world to respond...

With a good Number of countries that could "turn that country into a large parking lot"???
I doubt that any kind of extremely rash action like that would happen.
(Makes a good Video Game Though. A.K.A. "Homefront" the F.P.S. God I hope they make a sequel.)
Then again...
That countries leader is a young one. The question would be about how crazy his generals or advisors are.
What rank does the propaganda stop?
Those, I think, would be better questions to ask.
It would be a shame to loose a classic old world like Korea. I love history. I still have a number of places I would like to visit before my time on this earth is finished.
When I was a kid.
I never thought I would see over the Berlin Wall.
But,
I also thought Hong Kong Lease would never end either.
Allot of things that I never thought would happen... happened.

I doubt North Korea would do such a thing.
But..
I have never been there. I do not know the people.
More importantly I do not have any working info on the people in power other than the stuff you can get on the news witch is bare. (Ask D. Rodman the Basket Ball Player. He might have a better idea than any of us at this point.)
Good Luck.

Good Luck To All.
I'm done. Stick a fork in me.
Peace.

http://www.youtube.com/watch?v=Uzqx-lDoCr8

Man... I'm sure Jong is smart enough not to start a war on one of the most highly supported superpower of the world. I'm sure he wants to live and intimidate, not die and give in to his threats.

Do I expect North Korea to actually launch a nuclear attack?, Well no I don't because I don't think they have the resources nor the capability to get a nuclear war head of the coast so never mind across the Atlantic and or Pacific ocean. And I don't think any nuclear war heads produced by North Korea actually work. Furthermore I think North Korea is bluffing and their nuclear threats are getting quite tire sum and I'm sure they have threaten other nations with this Nuclear threat like China but they won't actually do anything because North Korea knows it needs western doctors and technologies and they need China because its there major food and raw material supplier so if they go the country pretty much screwed itself. 

I really do not think they'll ever do such a thing. They're not a smartly guided country, as they cut ties with China, their only supporter. They make these threats constantly, and they obviously must have thought that the fallout from nuking South Korea would destroy North Korea.

They're bluffing, and they always will.

First: wow, my thread has grown so much larger than I could have expected. Second: several people have stated doubt that North Korea is capable of such a launch. However, United States military intel suggests that they are, albeit rather unreliably.