Why Steve Jobs Is So Important to Apple

Apple announced Monday that Steve Jobs is taking another medical leave of absence from the company, his third in the past 7 years.
Apple did not disclose what is wrong with Steve, or what his prognosis is. In Steve's note to Apple staff, however, he sounded more emotional and less certain than he did when announcing his prior leave, and this has obviously left everyone who cares about Steve and the company very concerned.

How will Apple do as a company if Steve is not able to return?
This, obviously, is a critical question, and there's no simple answer. In the short term, six months to a year, the company will likely be fine.  After that, however, it's anyone's guess.

Steve Jobs' greatest strength is his product vision, which includes a magical ability to create gadgets that people don't just want and use but love. In the midst of a tectonic collision of the media, technology, and communications industries, Steve's vision has allowed Apple to invent whole new categories of gadgets that had never existed before, including the iPod, iPhone, and iPad. These products, and others, have made Apple the most valuable tech company in the world.

Now that the products have been invented, can someone else steer the Apple ship?
Again, over the short-term, yes, without question. And if Apple's future growth comes primarily from minor updates to existing products, the answer is probably still "yes."  Apple is a massive, global company with tens of thousands of talented employees, and they will likely keep making great iPhones and iPads with or without Steve.
But if Apple's future involves whole new categories of products -- as it very well might --Apple without Steve could be much less of a company than it is today. 

The collision of TV and computing, for example, is leading dozens of companies to jump into the fray, and this particular battle has not yet been won.  Apple's own product in this war -- Apple TV -- is still a work in progress, and it's not clear how the product will evolve.
Apple has many strong executives beneath Steve, and it may be that one of them possesses the same (or similar) product magic that Steve does, but at this point there's no way to know. And Apple's tremendous success over the past decade -- combined with the repeated failure of companies like Microsoft and Nokia -- has illustrated just how how rare Steve's talents are.