See http://abcnews.go.com/International/wireStory/north-korea-leader-kim-jong-il-died-15185456#.Tu6xJ9U_ihN
Which is a gamble, as in some ways Kim Jong-un is more of a radical than his father. It's definitely going to need to warrant some focused interest. Also, when an oppressive leader dies, it can often lead to a revolution against the new establishment.
I've only read/heard very little about his son, but what I have come across seems to agree with your take. Wish I knew more about the situation there to draw a bead on the likelihood of a 'Korean Spring'.
I may have some responsibility in this. I was talking to a Korean woman just yesterday, and suggested to her that because she is a long distance runner, that she could make it into N Korea and kill him. I didn't think that she would go through with it.