In a report for "PC Mag" (http://www.pcmag.com/article2/0,2817,2361204,00.asp), Sascha Segan says that the rise of the iPhone OS-based iPad could be the beginning of the end for the Mac platform. I understand his reasoning, but that's just not going to happen.
Segan says that if Apple could have a do-over, it would use the iPhone OS for its computer line. He thinks that the iPad should be thought of as "the new Mac -- a "new mode of home-based computing that Apple hopes will bubble up through its product line."
"This means no independent software stores, fewer open-source projects, and perhaps a blanket ban on BitTorrent, Flash, and Firefox," Segan writes. "It means a much more restricted peripheral market. The Mac will no longer be a PC as we know it -- it will be an 'end-to-end experience' like the iPhone."
According to his prognosis, the MacBook and Mac Mini lines will be the first to move from the Mac OS X proper to the iPhone OS, as they are lower-cost and appeal mostly to consumers. And Mac Pros will last the longest, "as professionals tend to require a wide range of peculiar hardware and accessories," he adds.
I can't see it happening. The iPad is a device for media consumption with some limited productivity features (such as the iWork apps customized for it). The iPad might make a great companion to a laptop or (especially) as a desktop Mac (I'll let you know as soon as I have mine in hand).
However, none of the iPhone OS powered devices have the oomph to do major productivity work. Can you imagine trying to do video editing or working with FileMaker on the iPhone OS? At least as it is in its present form.
The Mac has a long life ahead, as its form factor and Mac OS X offers benefits that the iPad and iPhone OS don't offer. At least in their current forms.
Rather I think that the Mac OS X and iPhone OS will be more closely integrated in the future. See my thoughts on this subject here: http://www.macsimumnews.com/index.php/archive/is_closer_integration_betw... .
For now, what I think the iPad will kill many netbooks. And probably the MacBook Air.