Funny thing about the market, it gets to tell you where the sweet spot is, not the other way around. Your scenarios presume that the iPad's mobility will trump the disadvantages of the small screen size to the point it will replace existing solutions with bigger screens. I'm not convinced that's the case. For example, when I visit the doctor or dentist, I don't go to an "office", I go to an examining or operating room. You know, places where they like nice big displays so everyone there can see the details of the x-ray pics? Those rooms are already networked and they stay put day after day, so mobility is not a desperate need.

Some of your examples seem contrived, like the office meeting where someone is dragging their power brick -- as if the iPad was the only device with a battery that lasts all day (and that the office worker didn't just unplug their laptop at their desk, where it had been freshly charged).

Police in their cars don't need a smaller display, and when they're out of the car they don't need yet another thing dangling from their belts. Delivery drivers already have solutions that are designed for their specific application and I suspect playing movies as well isn't a high priority at FedEx HQ's IT planning meetings. Etc, etc.