Paper note-taking and idea sketching is going to be around for a long time unless someone creates a system that can do just as well on computers. It will probably be on a tablet machine like the iPad, though it would likely work best where some kind of stylus is involved, for more natural drawing. Otherwise, trying to sketch things with a finger would feel more like trying to draw on a mirror with a sausage.
Mokalus of Borg
PS - I frequently find myself with an idea I can't write out on computer.
PPS - The closest to paper is Paint, and that's just sad.