I have lived here for six years and I can tell you, again, this year as the last (and the last)....life is normal. Every year in April, North Korea has their largest holiday and this same conversation comes up in the American media.
On the streets, with my co-workers, with daily life....everything is normal. No one is worried in the slightest. No one cares in the slightest. They're more concerned with the new presidential election and the Sewol anniversary.
Also, North Korea is really good at blowing hot air. Every missile they have fails at launch. They don't even have Internet, how can they possibly be masters of war and defense technology? Kim Jong Un is living high on the hog in a poor, poor land. He won't give that up. And he knows that if he does ANYTHING to South Korea/Seoul, he'll be wiped off the Earth in a matter of minutes, even by his allies.