Currently nobody knows how computer friendly it is, only Apple employees have even touched the thing. All you've really got are Apple's promises. The core of Dvorak's criticism is true, Apple is entering a high competition well saturated market with much lower margins than they're used to getting. I'm not convinced that means they're going to fail, but it's not going to be the coast they had with the iPod.
Can their margins really be that low? I understand that the iPhone is supposed to cost $500. That's over double what I paid for my Windows Mobile device almost a year ago, and as far as I can tell mine does everything the iPhone is supposed to do. More, if you count the fact that Windows Mobile is compatible with all the Office/Outlook business apps and has hundreds of third party mobile apps available.
If they're not making one heck of a margin on that, they're doing something wrong.
I'm not convinced that means they're going to fail, but it's not going to be the coast they had with the iPod.
Obviously Apple doesn't think that it will be, either - their initial target is to capture only 10% of the market.