On the "Will Apple do it all at once" comment.
ABSOLUTELY, right now they will. Their CEO has been called the most essential-CEO in history, meaning the company cannot survive without him. You can agree or disagree with that fact, but the shareholders are pretty convinced. Their stock value only dropped a little before recovering (last time I looked), but they are on a thin rope with investors. They are waiting to pull the trigger if spooked, releasing all of these products all in the same quarter or two, will produce tremendous quarterly reports and record high sales for Apple, which will help get the shareholders to trust Tim Cook, and to understand that Apple can survive with Steve only in the background.
So, yes, I forsee before third quarter 2011, iPad 2, iPhone 5, 10.7 (Lion), Macbook refresh, other relevant refreshes for products around or over 12 months (I don't know the current generations age of the iMac and Mac Pro, but those very well could be refreshed as well.) We may even see another big product announcement, like a touch-screen Air for Lion. (I'm making that up, PLEASE don't quote me, OR bash me and say it's not coming. I have NO idea what's coming, but I'm saying it could be something that shocking, after he returned from his last leave of absence we got an iPhone. Just sayin.)
When a guy like Steve Jobs steps down, he plans it. Analysts believe they were making plans for his leave of absence in the first week of December or earlier. He may not have told the employees or made it official, but he surely spoke with the board, and certainly Mr. Cook. When the Verizon iPhone event hit was when I first thought something was up. I know "it's not an Apple event", but they sent the number 2 guy, didn't they? If you don't think you need a major company presence, you send an engineer, or Johnny Ives or someone like that, you don't send chain-of-command number 2 unless you had originally intended to send the CEO. I'm sure he was taking every opportunity to rest, relax, finish up whatever loose ends he needed to, so he can take some time off.
-John