Yes. When the perceived value of Apple stock is so tied to Steve Jobs, the company must disclose it to potential and actual investors. It is not a privacy issue. If it turns out he needs a liver transplant, many people, who might not have invested, may loose money, and Apple will be open to lawsuits.
How about letting the Board decide whether or not its a Shareholder issue? Isn't that partially the responsibility of the board to determine what is or isn't a share holder issue?