N.korean attacks will call for indepth investigation, in which Seoul will conclude that it was, in fact, North Koreans who fired on the island, further provocation may make them react. Beijing and Moscow will hold their own independent investigations and will come to a conclusion that it can't be determined who fired the artillery and Venezuela President will claim that it was a U.S. conspiracy. Post this, the honorary UN will continue to send aid to North Korea like it never happened.
Based on my knowledge about South Koreans, they are not wimps. They're dying to retaliate, but this is not just about them. Their reaction will decide the political course of rest of Asia and potentially the globe. They kept silent after the warship sinking incident, it will be interesting to watch how much more provocation will be needed before they hit back.
This is not an official war but between the ongoing political games and war, I and other sensible people will choose the games. Right?