It's all about Apple running out of steam - fact obvious wherever you look at it...
1. Lion - although I will be sticking with OS X, quite frankly, Microsoft Windows 8 demos made me more excited...
2. iPad - while OKish device it has reached its peak and it is on its way down from now on due to huge number of equally good or better competitors flooding the market.
3. iPhone - see above...
4. Macs - while great machines they are hugely overpriced and might not be as easy sell as they used to be due to horrible economic situation that will only get worse.
5. And finally, yes, Steve is on his way out...
All this = stock going down and it won't stop going down for quite some time!
1) I think most people in the tech industry are not as juiced about Windows 8 as you are. Most responses I've seen (not just on Mac forums) have described it something along the lines of "Windows 7 with a WP7 dashboard". That might change closer to launch, but as of now the reception is quite tepid. Not to mention that there there is a dearth of hardware that can do the mouse+touch dance, and you are comparing something shipping in July 2011 to something shipping who-knows-when.
2) While it's arguable whether or not iPad will continue its success, I don't now anyone who can back up the argument that iPad competitors are about to take over. There are a huge number of tablets, sure. Maybe each model has sold 1,000 for a grand total of 10% of what the iPad has sold.
3) Android phones are waaay more successful than Android tablets. But even then, iOS and Android are roughly neck-and-neck. Comparing hardware to hardware, no model(s) match the iPhone line. The iPhone also ranks higher in customer satisfaction, usage, app attachment, etc. Comparing platform to platform, iOS (including iPad and Touch) is still more popular than Android. That, and they have been dealing with some quality control issues with their Market. So I give Android credit for flooding the smartphone market with numbers. But it's still quite competitive.
4) I might have believed that 2 or 3 years ago. But Macs are increasing sales despite an overall PC industry decline and bad economy. I think that theory has been disproven.
5) That's one area where I might agree with you. I think he'll stick around for quite awhile though. But the uncertainty does loom over things.