No, disagree fundamentally. A CEO has as much right to privacy over personal matters such as their health and family as anyone else.
But they also have a responsibility to be open about any of those matters that may affect their performance. But only when it does or is about to affect their performance.
I think maybe Jobs may be a bit late on the latter (although equally may understandably have been waiting for a definite diagnosis and positive treatment plan) but he, like every one of us, had the absolute right to privacy at every stage beforehand. To say otherwise is frankly ludicrous.
Should he be on Twitter, logging every sneeze, cough, ache or pain do you think? Or perhaps restrict it to, you know, what actually may be relevant to the performance of his duties? Just like he has.