With
Jharker and Ricewind's iPDF enhancements, it's now much better to take notes with ipdf. Not only do you get a true full screen, but the power savings help greatly (testing battery life as we speak).
I've made a 50 page lined paper pdf with this site here:
http://incompetech.com/graphpaper/lined/ so that it fits well on the screen. There is a url at the bottom that I did not remove. The site itself only has the ability to output a single page, but I used my handy linux pdf printer to create more.