Jim Walsh, an expert in international security at the Massachusetts Institute of Technology, pointed out that concerned speculation by the international community as well as heightened sensitivity from North Korea may be exacerbated by what appears to be North Korea's lack of a succession plan.
"The last thing the North Koreans want to hear is outsiders speculating on their family and political transition," Walsh said. "It's fair to ask these questions [about Kim's health]…but it's very important that the U.S. government and other parties have a steady, predictable, finessed policy here that doesn't rattle or miscommunicate its intentions."
Experts remain divided on the likelihood of various governing scenarios, which range from the collective leadership of generals and top officials in the National Defense Commission to the ascension of Kim's 27-year-old son Kim Jong Chul. He was appointed to a high position within the Korean Workers' Party last year, the same post that his father held in the past.
But at this point it is unclear what the international community could expect from North Korea without Kim Jong Il at its helm.
Assuming he is still alive and in fair health, Alexander Mansourov, an associate at the Washington, D.C. -based National Committee on North Korea, suggested Kim may make a public appearance in North Korea in the coming weeks.
"If Kim Jong Il is in good shape and for whatever reason decided not to show up at this parade, then I'm sure it would be in his interest to let the world know he's still in control and he's still alive. Within weeks, we would probably hear about his meetings or his travels around the country," he said.
Columbia's Samuel Kim agreed. "If there is no credence to this rumor, something should come out to disprove it."
North Korea observers are also surprised that the 60th anniversary festivities were significantly less large-scale than previous anniversary parades. Joongang Daily newspaper quoted a South Korean military source saying that the actual preparations seen via satellite had been quite large in scale, but Tuesday's parade was unexpectedly ramped down.
"The North Koreans have an incentive to demonstrate or make a statement that they're militarily prepared to counter American aggression. In my view, they had every reason to show their military might on a very large and impressive scale but that just wasn't the case. In that sense, it was somewhat surprising," said ABC News consultant Han Park, a professor at the University of Georgia.
Still, Park was not entirely convinced by the rumors.
"North Korea is known for misleading world opinion and managing uncertainties about their intentions or whatever the outside world likes to know," Park pointed out.
"It's a very psychological state and this could be a spectacle move, possibly designed for another strategic end."
ABC News' Kirit Radia and Jonathan Karl contributed to this report.