I've been a Mac/Apple fan since using them in college, enough so that part of my reason for picking my last two employers was the ability to work on Macs. I was an early adapter of the iPod and iPhone, and I was pretty excited in the runup to the iPad announcement.
Then, like many others, I was a bit underwhelmed. Part of it was that I'd read too much in advance, and so there was really nothing about it that was new (and therefore exciting). But part of it was that I couldn't see any real role for it in my life - I've got a laptop and an iPhone, and I don't need an in-between machine.
But, over the last 6 weeks or so, I've read a number of pieces that convince me I was looking at the iPad incorrectly. The first phrase that shifted my thinking came from the child of a tech blogger: "Dad, it's that thing from the movies." Every sci-fi movie for 30 or 40 years has featured flat, portable, effortless data screens; the iPad. This post, in particular, captures well what the iPad represents (as does this followup post). No guarantee it gets there, of course, but Apple has been hitting its targets pretty reliably lately.
The original Macintosh computer was advertised as a computer "for the rest of us." And, relative to command-line DOS, with its C: prompt and arcane, 8 character commands, it was. But the iPad promises to be the first computer that really is for the rest of us - for everybody's who's ever hunted for the file they've just created, for everyone who's closed a window thinking that they were closing a program, for everyone who's hunted through 50 drop-down menu items searching for the tool they want to use.
I'm still not sure I, personally, need one: as an architect, I'm pretty much a power user, and I don't see anyone making a full-featured gesture-based CAD program in the near future (I'd love to be proven wrong; Sketchup has some of the appropriate characteristics, but it's not actually adequate for contract documents, and I hate the idea of a building model in one program and the "real" drawings in another). But this is surely the first computer I'd consider recommending to my mother-in-law, and I think it won't be long before the iPad starts to draw a lot of customers who are stuck with a lot more computer (and a lot less usability) than they need. A designer friend recently noted that design isn't about making things pretty, it's about making things more useful; I'm not sure that there's a better example of that than Apple's iPhone OS approach.
PS - All that said, until the printer interface becomes seamless, computers will remain a source of frustration. Sometimes, you just need a piece of paper, and I don't think the iPad gets us any closer to making that process non-frustrating.