Apple fans and the technology community responded in shock to the announcement that Steve Jobs was stepping down while he fights a “hormone imbalance” that has made him lose weight rapidly.

Bloggers, Macolytes and analysts lined up to express surprise, saying that they were concerned about the company’s long-term future.

Dan Frommer, from Silicon Alley Insider, a respected tech blog, said: “Apple will gradually lose its lead - especially if it doesn’t quickly put in place a plan to move forward without Steve. “Pundits will argue all day that Apple is more than Steve Jobs. Fine. But Steve Jobs is Apple. He might not write code or sit in chip fabs. But he makes the big, important decisions that make Apple products Apple products. New decision-makers will make choices Steve wouldn’t make. Talent will leave. Etc.”

Resentment was expressed about the way that Apple had dealt with rumours about Mr Jobs’s health in recent weeks. The fansite, AppleInsider, suggested that the company had opened itself up to the risk of lawsuits, although it admitted that the “law is unclear on what personal medical information a company must (or must not) disclose about members of its top brass”.

Jim Goldman, on the Tech Check blog, said that industry executives had said that Mr Jobs had been in “serious denial” about his health in recent weeks. He added: “Apple didn’t have to share any private details about his health. Legally, the company was solid. Ethically, morally, maybe not so much.”

Keith Bachman, a BMO Capital Markets hardware analyst, said: “At a minimum, the announcement raises credibility problems on how Apple is dealing with the public.

“We also believe that investors need to calibrate that Mr Jobs may not come back at all. How do we know for sure if he will come back? We don’t.”

Although most of those commenting suggested that Mr Jobs’s departure was a serious, if not fatal, blow to Apple, others argued that the culture that he had created means that the company is likely to stay strong without him.

The TechCrunch blog said: “Steve Jobs has imbued his company with so much of himself and his ideas that, like the movie, he has created a veritable army of Spartacus’s. They know what to do.”

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