Of course, there are already fears that Apple will die soon without Jobs at the helm. It is a company that had heard that since IBM released their PC, when Jobs was fired, etc. The reality is that even during those periods, and moreso in the '90's when the company was considered dead, that they were still pulling in a profit near or above $1B. It's market just did not grow.
The thing is, Jobs worked for HP at a time when HP was creative. HP would allow it's engineers a 1/2 day to explore an play with all of the resources available. This was a concept that Jobs brought to Apple, and the concept lived through the non-Jobs years (Newton, etc). While he is portrayed as one who controlled every aspect, he did but not without consideration from others or recognizing that someone had a better idea (OS X interface came from a mock up by a graphic designer. and Mac OS X, while built from the NeXT foundation, also incorporated many ideas from prior to his return). This concept will not be leaving the company with his death just as it did not when he was fired.
The biggest thing Jobs was able to do when he returned to Apple was to mold it the way he wanted the company to be. He changed the business culture to what he was doing with the original Mac development. The company has always had an eye for talent at the worker level, but not in the executive level. That has changed, and while made up of many that came through the ranks (or returned), it now has balance. It also, as it has had some the 80's has many users that have provided improvement to the products over the years (that OS X dock was available by an independent developer in OS7, and could be added from an Apple download with OS 9). But then again, Jobs never had a problem with using other people's ideas given to him (GUI from Xerox-Parc, pushing postscript (unified wysiwyg printing) with Adobe (and developed by Xerox-Parc), etc).
The man had fingers in many places, and drive improvements, ease of use, etc in all of them.
Jobs was a visionary of not just the computing industry, but also in the Movie industry. He took a chunk of Lucas's empire and turned it into Pixar. It is not hard to argue that Pixar showed the industry how computer animation can be done well, effectively, and applied to just about any movie. Sure Pixar has released primarily animation flicks, but ILM has conscripted Pixar, and Digital Domain was given much assistance to get started from the staff. But beyond all that, it was the insistence that an animation movie like Toy Story could be made with the technology at the time that showed that computer animation was here and now for flicks.
And just one more thing, the gaming industry with the tools developed from graphic design and easy of reusable code\animation\built-in functions\portibility that were much of the foundation of the NeXT system. Doom was developed on the NeXT, and the ability to customize the maps and graphics with built in tools was due to the system design and how much Id Software loved it. Bungee is another company that utilized the NeXT. I could go on.
