Is it even possible? Forbes does a little bit of speculating on just who might take over when Jobs takes his leave from Apple, and candidates aren't exactly jumping out of the woodwork. Jobs is about as visionary as they come -- only a guy like Steve could lead Apple from the iMac to the iPod to the iPhone, breaking records and status quo the whole time. Phil Schiller and Scott Forstall are tossed out as two names currently within Apple's ranks, but Jobs is almost as much of a company mascot as he is a CEO. As consultant Patrick Sweeney says in the article, anyone who steps into the turtleneck has to fit completely into the culture of the company, or it won't work.
And forget the day-to-day and design decisions -- who's going to stand on stage and say "boom" at WWDC and Macworld? Here at TUAW, we're pretty sure the rumors of Jobs' ill health are exaggerated; he's probably not going anywhere anytime fast. But at the same time, it's hard to imagine an Apple without him at all.
AppleiMac 27-inch with Retina 5K display (late 2014)