Since the days of watching Star Trek The Next Generation, where the Padd was the interface device of choice, I knew that someday we would all have access to something similar. I say iPad since so far there really isn't any equivalent competing device, the Kindle Fire is hot but it's not as general purpose. In any case since I write for iOS I'm biased anyway.
The revolution lies in being able to adapt a lightweight portable device with an expressive UI to a host of business uses formerly done with desktop or laptop computers, special built devices (think UPS) and clipboards with paper. Although the bulk of work today for the iPad is targeted at the App Store and consumers, the real market is in the everyday workplace. You can see the start of this around you but it's only a drop in the bucket.
One thing I do see is still missing is rather obvious - a handle. In order to use an iPad to process orders, manage inventory, or perform other operations while standing is a firm grip on the iPad. I can see two ways to build a handle, either on the side or the bottom. Currently the design of the iPad does not lend itself all that well to solid connections either way, but I'm sure this can be done. I wish Apple would see this and either design an iPad with a way of securely attaching a handle or actually offering it as an option. That way the user can firmly grip the device in one hand while using the other to operate it. Making lighter devices will help too but today it's way too easy to drop it, especially in an industrial environment. Targeting an iPad towards a business audience seems unlike Apple's usual generic approach, but maybe Tim Cook will see things differently.
You can already see people looking at the iPad to change how they work. Airlines are looking at using one to manage all of the documents and maps that pilots currently need to lug around. Having an iPad textbook (which of course the Fire could be great at as well) means no more lugging around books. Even the simplest taking of orders in a restaurant could be made so much easier. The world is full of manual paper operations, either reading or writing, where a fully electronic, connected device would make people more productive as well as allow better integration with other systems.
The more pervasive an internet connection is and the lighter the devices may get mean more people can use them everywhere, from inside a warehouse to a customer's home. Add a lightweight bar scanner or credit card reader or even a paper output device and the iPad can manage almost any retail function.
There are concerns of course, mainly battery life and security and breakage. If you are a pilot in an emergency what do you do if your iPad battery ran down? If you are connected all the time can someone hack your connection and steal valuable information? If the handle isn't well designed what will you do when your whole retail establishment depends on something now scattered in pieces on the floor? Like everything new these problems need to be explored and dealt with.
I once dreamed (long before the iPad) of having a generic flat device piled up everywhere and available to anyone. Each user had a ring or bracelet or something that electronically identified them so that when they picked up one of these devices it would immediately personalize itself to the state they left the previous one in. Basically any device would be "your" device, no matter where you picked it up. This way you don't need to carry one around, you just use whatever is lying there.
In any case using an iPad for a specific business usage replacing a less portable or even manual function is what excites me most. Today there are many developers horizontal market apps mostly targeted at a more generic population, and although I can certainly do those kinds of apps, I much prefer working on the iPad form factor, and helping the vertical market move forward. Today finding those opportunities is much harder to do as businesses are just starting to think about what an iPad can do for them but being able to advance a revolution is what I would enjoy the most.
Let me know if I can help.