With Jobs at the wheel, Apple became the master of design. It's not that Apple always brought something new to the table. Portable music players, for instance, had been around for ages long before the iPod took the world by storm. What Jobs did always bring was an eye for quiet, graceful looks that combined function and appearance into a single harmonious whole. No one, but no one, else has been so successful at that in either computing hardware or software.
Gimlet-eyed stock holders might not see the beauty in Apple's designs, but they have seen how Jobs turned a company around from near irrelevance to a technology stock gold-mine. Is there anyone besides Jobs who could step into his shoes and convince an already frightened market that Apple will be as great as ever? I doubt it.
Apple's friends are spinning away that Jobs is staying away because of politics, without any real explanation as to what those politics might be. Conflicts with IDG World Expo, the company behind Macworld? That seems silly. Apple's already leaving. What would be the point?
Could it be that Apple wants to hide a decline in his health? By not showing up, all Apple has done is fuel endless online speculation about his health. It would be better for Apple if Jobs showed up, if need be, in a wheelchair, perhaps in Dean Kamen's iBOT - it even has the right name!-- tricked out with Apple hardware, than to simply not be there.
No, all that really matters here is that Jobs, the master of control, doesn't appear to be in control. The reasons for this don't matter. If Jobs isn't seen at the ship's bridge, we don't see Steven Jobs' Apple, we see just another technology company. And, that is not the message that either Apple's users or investors want to see.