I am not a doctor, nor do I play one on the internet. But what seems more likely? That Steve Jobs is suffering from a "hormone imbalance" that has sent his weight plummeting and requires a leave of absence, or that his delay in treating his pancreatic cancer while he messed around with woo "alternative therapies" for nine months gave it time to metastize? Pancreatic cancer is nasty, nasty stuff. I don't think we're going to see another comeback this time.
Those are terrible words to write. And terrible news for Apple, which has never been able to prosper long without its founder. Apple's management works very well--obviously--but it's far too centered around one man. Steve Jobs has never managed--or from what I understand, even much tried--to build a robust corporate culture that could be self-sustaining without his presence.
There's a perennial debate in management theory over how much CEOs matter--whether the company would chug along much the same with almost anyone in charge. I suspect it depends a lot on the company. All CEOs make some difference, of course, but much of the success and failure we attribute to them is probably actually exogenous. Nonetheless, at a company like Apple it's very clear that fortunes generally rise and fall on Jobs, and the corporate culture is built around that fact. I don't think it's any accident that the help desks in Apple Stores are called "Genius Bar".
The problem is, there aren't that many geniuses of Steve Jobs' caliber around. Frankly I'm surprised that Apple's stock has fallen so little, just a couple of points on a price in the 80s.