I have an iPod Touch, and I'll admit it is the first "PDA" type device I've had (and I've tried a number of them) that is usable. Basically I carry books (Kindle application), reference material and entertainment, all in my pocket.

The problem I see with the iPad is the size. It is way too big to be a real portable device. Great for sitting on your couch "reading the paper" or browsing the web, but it is too big to slip it in your book bag or coat pocket like you might a paperback novel.

It seems to me until they produce this type of device following the form factor of a paperback (aprox 8" diag for the entire device), they are really limiting themselves to a very specific market.

Build one with a 7" screen, about 8" total with the same features as the iPad and I'd probably buy one.

-john