North Korea changes it mind more than the average woman. One day it appears to be cooperative and the next it is back to the same old miltaristic rhetoric. The same goes for Iran. These two countries are going to play this "I will, I won\'t" game until they are finished developing whatever their goal is.
I wish I could believe the NK announcement, but when you have a country and a leader whose main GDP is the military, you have to wonder.