I have big D&D plans for me and my iPad. Unfortunately, I'm still waiting on the 3G model, so I can't tell you how well they work out.
When I heard about the iPad, I did some math. I had always wanted an smartphone (not for the phone but for the 3G) to stay connected to web/emails when I wasn't at home or near a computer, a new laptop for writing on the go (the best time to write, for me), a kindle to continue my consumption of books wihtout finding a place to store them, an ipod because I just never got around to buying one.
The iPad was a strong draw from day 1 because it combined a lot of these functions that I had put off buying devices for and now allowed me to sort of save money by just buying one device that does all of these things, but at 729 for a 32gig, 3G, I was still on the fence.
What finally pushed my over the edge and convinced me to put up the money for a pre-order was the idea of using it at the table at D&D, eliminating the need for physical books and a paper character sheet.
I've always felt that a computer at the gaming table had the potential to be the most useful play-aid you will ever own, but I've always been dissapointed by just how intrusive even a little netbook is at the game table. I even bought myself a DS-Lite and a R4 card and started writing my own custom combat trackers and character sheets in C, but the screens were just too small and the video-game optimized interface wasn't cutting it. The iPad is the first device to come along that is as discreet and portable as a handheld device, but nearly as big and easily manipulated as a real computer.