Silicon Valley Insider: "As expected, Apple shares opened lower this morning after the company announced Tuesday afternoon that CEO Steve Jobs would not deliver his annual keynote speech at the Macworld conference. Apple (AAPL) shares are trading down 5.8 percent to $89.90. Key concerns:

"° That Steve Jobs is sick. There are many other potential explanations for Jobs not speaking at Macworld -- politics, weak products to announce, etc. But -- and we really hope he's fine -- who knows.

° That Apple doesn't have anything earth-moving products to announce next month. Which is probably true. And a valid reason for Jobs not presenting. But not exciting news for Apple investors."

Cult of Mac: "Despite Apple’s attempt to convince investors otherwise, Oppenheimer & Co. told clients new questions about CEO Steve Jobs’ health made the Cupertino, Calif. company a risky long-term bet. The investment house downgraded Apple’s stock to 'perform' from “outperform” following Tuesday’s announcement Jobs would not appear as keynote speaker at the Macworld 2009 tradeshow - the last year Apple would attend the annual event. 'Whatever the reason, the unexpected announcement has underscored the greatest risk to Apple’s long-term success -- its dependence on Jobs’ health and its apparent lack of a succession plan,' analyst Yair Reiner wrote investors."

Time: "Steve Dowling, an Apple spokesman, deflected any questions about Jobs' health. When asked if Jobs canceled because of illness, Dowling said, 'Phil is giving the keynote because this is Apple's last year in the show, and it doesn't make sense for us to make a major investment in a trade show we will no longer be attending.' Asked again about Jobs' health, Dowling gave a similar answer, never using the word Jobs or anything related to his condition."

Edible Apple: "Though seemingly coming out of left field, Steve Jobs’ decision not to speak at the Macworld keynote this January makes a lot of sense for a number of reasons. First of all, Macworld expectations got out of control and put too much pressure on Apple to deliver amazing products at arbitrary times. Second, it’s the most recent step by Apple to introduce other Apple personalities, and to let people know that Steve Jobs is not the only person responsible for Apple’s success. This is significant because the health of Steve Jobs was starting to overshadow what Jobs was actually announcing. Leaving Macworld and giving Keynote duties over to Phil Schiller was Apple’s way of taking back control of an event that simply got too big and hyped up for its own good."

Fortune"... even if you accept Apple’s reasoning for abandoning Macworld, that doesn’t explain why Jobs isn’t giving the valedictory keynote. Or why he waited until three weeks before the event to spring the news of his absence and his keynote stand-in Senior VP Phil Schiller -- too late for the thousands of Apple enthusiasts making the pilgrimage to San Francisco to get their money back."

ZDNet: "Well, here’s my take on why Apple’s decided to do this …

° Tradeshows are dead. OK, not actually dead, but terminally ill. I know that some people disagree, but the reach of tradeshows compared to the reach of say the web is tiny. Sure, there are exceptions, but on the whole the era of tradeshow is over.

° The Macworld Expo wasn’t an Apple thing. Macworld Expo is run by IDG World Expo. Apple likes to have a lot of control over events it puts on and chances are that Macworld Expo didn’t offer Apple enough control.

° Apple’s grown beyond the cult of users that flock to tradeshows and hang on every bit of info coming out of Apple."

Macenstein: "Uh oh, looks like Apple-themed conventions are falling like dominoes. Our good friend Arnaud over at the French site Mac4Ever has alerted us that the powers that be behind the Apple Expo in Paris have announced they will not be putting on the event this year. The 2008 Expo was the first year that Apple did not attend the French gathering of the Mac faithful, and apparently the turnout was so dismal that the promoters will no longer seek to produce the event without Apple’s presence."

Future Changes: "Here are three reasons why it’s a good move - especially in this weak economy:

"° Trade shows are diminishing in importance. I went to Macworld last year and was underwhelmed. Most big tradeshows don’t really do anything to reach the average consumer. They may be fun for the “insiders” but there’s much more valuable information and community to be found online.

"° Apple.com is a powerhouse. Apple is no longer a niche company that needs a tradeshow to reach a niche community. According to comScore, Apple was 5th busiest retail site on Cyber Monday following eBay, Amazon, Walmart, and Target, and beating Dell, HP, and Best Buy. The site drew nearly 3.7 million visitors - that’s many, many times more people than a trade show can draw.

"° Smarter than Layoffs. On Fortune’s Apple 2.0 blog, the article about Apple’s Macworld departure starts with: “In a surprise move that shocked fans and troubled investors”. This should please investors - it’s a prudent move by a company that obviously recognizes the need to cut unnecessary costs in a worsening recession. Which would you rather see from Apple - departure from Macworld now or layoffs?"