I think you can predict acceptance of a new product by what people will compare it to. For example, the iPod was compared to all of the other ways you could organize and carry your music around, and the iPod was just plain better.
Then Apple introduced the iPhone. It was compared to other phones, and in that comparison it won easily, unless you expected to do a lot of e-mail.
Yesterday, Apple introduced the iPad. What do you compare it to?
The iPad borrows a little from phones, and a little from laptops, and a little from their own iPod and iTouch, and a little from the Kindle. It's better in some ways than all of those things, but less portable than its smaller cousins, less functional than a laptop, and more expensive than a Kindle. There's no comparison that is a clean win.
I think the human brain will automatically compare the iPad to a laptop, mostly because of the size. And I think most people will come to the conclusion that since an iPad won't replace your laptop, and it's too expensive for a toy, it has no place.
Betting against Steve Jobs is a fool's game. But the iPad doesn't feel like a genius creation. I think Jobs was focused on his health when the iPad was conceived. It looks like committee work to me.