After seeing so many posts about North Korea following Kim Jong Un's barrage of threats, I thought I'd do another AMA in case there's any interest--my previous ones had a lukewarm reception to say the least. My background: I was a professor of literature in Seoul for three years, and I volunteered at an organization that supported North Korean defectors living in South Korea.
You can read about me here: http://chronicle.com/article/Growing-Pains-for-Foreign/136453/ (paywall) and here: http://thethreewisemonkeys.com/2013/02/11/lost-in-translation-the-case-of-the-medieval-professor-and-the-ivory-korean-tower/ (non-paywall).
While I don't know all the details about the North Korean military, their capabilities, or how real these current threats are, I do have some insight from what former soldiers told me and about Korean culture in general--both in the North and South.
Edit: Time for me to sign off--thanks for the questions; I hope I delivered!