Well, it's an interesting event. His son, Kim Jon Un will take power, but not at once. In the meantime, it's Il's brother-in-law who runs the country. I don't think anyone want to start world war 3, it's actually more likely that they'll try to reunite with South Korea now. They'd earn a lot on that, and South Korea have even put aside 50 billion dollars for when that happens (to save their economy when it's merged with North Koreas communism-based economy).
But don't expect anything to happen soon, though.
But don't expect anything to happen soon, though.