About the same as your finger, except you can write slightly smaller. So far, genial writing is the best note taking app i've tried. Once you get the timer set to go to the next line, you can write as fast or faster than a notebook and you never have to change pages. No provision for adding drawings is the main downfall. The big problem really lies with the nook as it doesn't seem to have a tight sensor grid, so fine drawing and writing isn't possible. It works for straight notes and basic drawings, though.
I suppose if you need really detailed drawings, you can go into andcad, the stylus works well there. Unless somebody figures out if the screen can be made more sensitive, I think its not quite there for note taking and drawing except for simple, quick stuff, or in the case of genial writing if you just need to write out a ton of text only.