I still don't understand the tablet form factor. I concluded that it's not for me some time ago, but am waiting for the general population to come around to one glaring flaw: you have to hold it. For me, it doesn't matter how light a tablet is. A five pound laptop will always feel lighter since it will effectively weigh nothing because it's always on some kind of platform during use, either my lap or a flat desk/tabl…
That could also be said to be a flaw in books, but that's an interface that had some staying power. And most people probably use a tablet, like a book, setting on a surface or propped up on something.