I'll probably buy the least expensive $499 wi-fi-only iPad as a replacement for my first-gen iPod Touch, and as an e-Book reader. I tend to do late-night news reading, e-mail checks and tomorrow's weather checks with my Touch because it's easy to use while I'm lying down. And I read several chapters or more in a print book before going to sleep, and the heavier books can be cumbersome.
The iPad would let me combine both tasks, and the larger bright screen would enhance both experiences. Plus, I'll be saving money on book costs and there won't be a stack of read books to dispose of at yard sales. As a bonus, I'll be able to read my four comics feeds and do some quick web browsing without having to balance my heavier (and cold!) Unibody MacBook on my sternum in the morning.
My Mini 10v has been upgraded to Bios A06 and the latest version of Snow Leopard, but the battery life is horrible, the screen is too cramped, and the human interface devices leave much to be desired. I tried to use it for the activities noted above for a couple of months, but just got frustrated. Now I tend to use it as a tote-around laptop for keeping in touch with things Internet while I'm watching TV, or moving around town when I know I'll be near wi-fi hotspots. I see the iPad taking over that role too, and doing a much better job than the 10v, whose keyboard I rarely use for typing much more than a line or two of text at a time.
My grandson, who loves the 16 GB SSD
Mini 9 I replaced with the 10v, will get the 10v and its 10-times-larger 160 GB hard drive when I get the iPad. But I don't see the iPad replacing my 13.3 inch Unibody MacBook or my 27-inch 3.06 GHz iMac since they are full-blown computers. The iMac, with its 1 TB hard drive, also will serve as the iTunes sync/backup computer for the iPad.
The initial joy and wonder of having an inexpensive "MacBook Mini 9" and "MacBook Mini 10v" has been tempered over the last year by their design compromises and impaired human interface experiences. But combined with my similarly disappointing iPod Touch experience, I've learned what I would like to have in a handheld device that combines the best of both, and that looks very much as if it will be an iPad.