Steve Jobs, Apple’s iconic founder and CEO, unexpectedly said he’s taking a six-month medical leave of absence, said Dan Frommer in Silicon Alley Insider, because his health problems are “more complex” than he thought two weeks ago. Apple has a “deep, talented executive bench,” including COO Tim Cook, who will take over day-to-day management. But for many investors, “Steve Jobs is Apple,” and it’s hard to imagine the company without him.

Apple’s prognosis depends on its CEO’s, said Saul Hansell in The New York Times online. If Jobs returns in six months, Apple should stay on track. But “the risk to Apple is far higher if we imagine the grim possibility” that its chief “obsessive visionary” won’t return to work. In that case, the board shouldn’t look for a “Steve Jobs clone”—there isn’t one—but pick a CEO with a different style. “Steve Jobs can be replaced, even if he can’t be duplicated.”

“Apple will still be there next year and the year after that,” said Emory Kale at TG Daily, and Apple investors should stop being “a bunch of selfish bastards” and let the ailing Jobs work on being here next year, too. Let the man retire and enjoy his wealth and accomplishments—without “people hanging on to every beat of his heart, and trading his company’s stock on the downbeat.”

“There’s nothing personal in the curiosity” over Jobs’ health, said Michael Hiltzik in the Los Angeles Times. “It’s just business.” And despite Apple’s “culture of secretiveness,” the health of its “uniquely important chief executive” is not just a personal matter. At the very least, investors deserve a clear plan of succession.