The demise of a tyrant inevitably inspires hope among those who saw him for what he was. But as much as there is reason to cheer the death of Kim Jong Il, there is no reason to celebrate the future of a North Korea without him. Kim Jong Il's demise marks the end of the reign of a tyrant who was as vicious as his father, Kim Il Sung. Together they constructed and perfected the North Korean tyranny over which they presided. But they did so with advice and operational support from other North Koreans. The others will doubtless remain in power. There is no reason to think they will change policies that they long have seen as the source of their political power, their economic advantages, and their survival.
I say the others will doubtless remain in power and perpetuate the hideous rule of the father and son because of what we seem to know about the last 24 hours. The death of KJI was reported by North Korean news outlets and by the regime in a very orderly way; the steps taken by the regime to accomplish this had to have been planned for some time. They also had to be the result of a strong consensus among the North Korean leadership. The publicly displayed support for Kim Jong Il's chosen successor, Kim Jong Eun, has also been pervasive and consistent, both before and after Kim Jong Il's death. The funeral was quickly set for December 28, and the government declared that mourning would continue until December 29. All of this signifies preparation for continuation.
One report has it that the DPRK government closed the border with China. Reports also tell us that guard duty along the Yalu has been doubled for the time being and all leave cancelled.
So, it seems to me that, although the U.S. Department of State likely will invoke "change" in the North Korean regime to justify its (previously announced) plan to resume aid to North Korea in exchange for North Korean promises to suspend part or all of its nuclear-weapons program (promises like those that North Korea repeatedly broke in the past), the regime's surviving leaders are unlikely to change North Korean policy or behavior, either with respect to its nuclear programs or its continued victimization of the North Korean people.