Don't have one, don't want one for personal use.
Now, for the classroom, that's another story. I have visions of a class set of tablets, tied to my computer (which projects onto the screen). I'd love to be able to throw up a problem, and then watch 25 kids scurry away solving it on the ipad, and flip around whose work I project and we learn from. It could be anonymous, engaging, and just more fun than pencil and paper for my 8th grade algebra students.
BUT...since the apps for math stop at middle school math (i.e. Math 8, not algebra), the technology I want doesn't exist (I've asked, the county has done research, they can't find it), and even if it did it would be insanely expensive....
NO, no need for an ipad.