Kyle Baxter:
The iPhone is the device you use to browse the web and check Twitter while running errands or at a friend’s house; the Mac is the device you use to get real work done; and the tablet is the device you use to read a book, edit a document, or watch a movie while in bed, on a plane, or in a coffee shop.
You won’t use it because it can do things the iPhone, or a notebook, can’t. You’ll use it because it’s much better at doing them.
There’s a chasm between the way people use the iPhone or Mac, a middle-ground between work and play, that Baxter astutely recognizes. Apple doesn’t want you to do everything on one device, contrary to current trends in technology; they want to make devices that aren’t just good at many things, but great at a few specific primary functions.