North Korea does have nuklear weapons. No doubt about it, but the condition, quantity, and power of these weapons are still shady.
Now on to the big question, will North Korea attack a foreign country? If they had ANY sense what so ever, the answer would be no. If they so much as sent a single missle to another country, the U.N. would immediatly have an enormous amount of military personel sent into the country within a couple of hours. Yes, hours. North Korea as we know it would be crushed and sent to the post-WWII status that Germany was in. No standing military, an imposed government, and armed guards from the U.N. patroling every city, not a pretty picture, is it?
As for any other country attacking North Korea, I can only speak for the U.S. because I don't know many other countries' relations with North Korea. The U.S. has a long history of not getting involved in international conflicts, not majorly, anyway(excluding Iraq). Unless, we are attacked first, we like to keep our hands free from fighting, preferring peace talks to open warfare.
To sum up, I believe that North Korea is a potential threat. Reckless, but still only potentialy dangerous. As far as I know, thay haven't recently threatened any nations, but that may change very soon.