it's a single piece of equipment that replaces at least four: a phone, a PDA, a camera and a desktop computer, and those people are willing to sacrifice some comfort for convenience of another kind.
The next step will be a 7" phone. No one will be able to hold that to their face so it will come with a handle at the back that will make it look like an iron. The handle will also double as a kick stand. Heck, perhaps I should patent that idea, sell it to Samsung and make a lot of dosh!