This is the kind of thing we hate to report but since we've got so much vested in Apple(we know his health is his own business - this is more what we'd like to think) -but here goes from Gizmodo:
According to a solid source, Apple misrepresented the reasons behind MacWorld and Steve Jobs' keynote cancellation. The real cause is his rapidly declining health. In fact, it may be even worse than we ever imagined:
Steves health is rapidly declining. Apple is choosing to remove the hype factor strategically vs letting the hype destroy apple when the inevitable news comes late