I've gotta ask myself: Is this solution superior to the thing it's replacing? A handwritten-note-taking app for an iPad does not pass that test, in my book.
Imagine you could carry all the notes you've been taking for the past four semesters at college on a 1.5 pound device, along with all your textbooks and private mails AND your entire music collection. All in a sleak device the size and weight of a hardcover book.
Still doesn't make a lightbulb go off?