North Korea: Overthrow or Just "Health Issues" at the Top?

When dictators go missing, rumors fly, as reported by North Korea News in September: Kim Jong Un a virtual no-show: Kim’s absence, continuing position changes lead to uncertainty and speculation about the regime:

As of October 3, North Korea’s Supreme Leader

KJU in the land of the funny hats and haircuts

Kim Jong Un has officially been missing from public view for 30 days, his longest absence ever. This has, as expected, led to many questions and speculation about what’s happened to Kim and what it means for the regime in Pyongyang.
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It didn’t take long for observers to notice the unusual lack of state media appearances by Kim and, consequently, to begin questioning it. A rumor soon spread that Kim, who allegedly developed a fondness for Swiss Ementaller cheese while studying abroad there, had imported large quantities to North Korea for his own personal consumption. Kim was also seen sporting a limp since July. This, combined with his physical size, smoking habit, and rumored love of cheese, has led to speculation that Kim may be afflicted with gout, which often causes pain in the joints of the feet and ankles.

Pyongyang did, uncharacteristically, publicly announce that Kim was indeed suffering from health problems, but they provided no details. North Korea later denied rumors that Kim underwent ankle surgery.

This situation has additionally led to speculation about who is currently in charge in Pyongyang and whether or not there will be any major change in the structure of the regime. The Seoul-based think tank North Korea Intellectuals Solidarity (NKIS) suggested that Kim Yo Jong, Kim Jong Un’s younger sister, may presently be responsible for running the regime while her brother is being treated for his health problems.

More on why this "known unknown" is a bad thing at The National Interest After Kim: Why the Mystery Surrounding North Korea is a Very Bad Thing:

Today, talk is rife that North Korea’s Kim Jong-un might be about to undergo the same fate as Khrushchev. To be sure, experts downplay the likelihood that Kim has been or will be overthrown. Yet the recent flurry of conjecture about North Korea’s future only highlights the extent to which outsiders do not know what takes place along Pyongyang’s corridors of power. The level of uncertainty is far beyond even that which characterized U.S.-Soviet relations during the Cold War and makes it almost impossible for the United States, South Korea and others to develop judicious policies for handling the infamously volatile North Korean regime.

Hope the ROK is on alert.

Yes, even with the new agreements to talk with the NORKs, South and North Korea Agree to New Talks:

South and North Korea agreed on Saturday to resume high-level talks this year, raising hopes for a thaw in the long-tense relations on the divided Korean Peninsula.
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The North Korean delegation’s visit and the agreement to resume talks were all the more unexpected, given the North’s recent vitriol toward the South Korean president, Park Geun-hye. On Thursday, the North called Ms. Park “a rabid dog” after she vowed that pressing the North to end human rights abuses would be a key goal of her government.

The two Koreas have technically been at war since the Korean War ended in 1953 with a truce rather than a peace treaty, and their relationship has been particularly sour during the past few years. But signs of a possible thaw have emerged in recent months.