so many uninformed responses on this thread.
Kim says shit like this because it is one of the tools he uses to control his own people and look strong internally. I doubt he has any intention of carrying it out. He did not grow up in isolation like the rest of the people in his country did. He knows if he has any chance of survival in any conflict he cannot look like the bad guy. He knows if the US looks to be the aggressor China will pledge their support to him which would likely cause us to de-escalate.
If he goes and nuke something in response to an insult NO ONE will support them and once China backs out he is done.
End of 2009 Predictions (Set, January 1st 2009)
Wii- 72 million 3rd Year Peak, better slate of releases
360- 37 million Should trend down slightly after 3rd year peak
PS3- 29 million Sales should pick up next year, 3rd year peak and price cut