Apple Bruised by Renewed Jobs Jitters

The Apple(AAPL Quote) premium suddenly got a Steve Jobs exit discount.

Tuesday started like any other day, filled with speculation about Apple's refreshed product lines, such as potential new mini Macs and a possible netbook launch to extend the company's hot hand into a whole new growth segment in the tech market. But the mood changed abruptly at 4:30 p.m. EST when Apple issued a press release saying Jobs would not deliver the keynote address for the upcoming Macworld Expo.

The absence of Apple's marquee product pitchman, just three weeks ahead of the annual showcase event, quickly reignited anxieties about the health of the CEO. The news wiped as much as 7% off the stock price Wednesday and earned the Mac maker at least one downgrade.

For Apple fans and quick-triggered Wall Streeters, the big problem with Steve Jobs is that there is only one Steve Jobs.

"The unexpected announcement has underscored the greatest risk to Apple's long-term success -- its dependence on Jobs' health and its apparent lack of a succession plan," Oppenheimer analyst Yair Reiner wrote in a research note Wednesday, in which he cut Apple to hold from buy.

Jobs was treated for pancreatic cancer in 2004. Among the more common and challenging after-effects of the surgery is that it leaves a person with a somewhat compromised digestive system. In June, when Jobs took the stage to introduce the cheaper faster iPhone, his dramatically thinner appearance led to speculation about his well-being. Both Jobs and Apple regarded the issue as a private matter.