Currently, any changes to the notebook are saved when a move is made, or when the "save notebook changes" link is hit. However, that link does not appear when it is my move. If I look at the board while it's my move, and want to leave myself some notes but not move right away, I cannot use the notebook.
edit: Perhaps the easiest solution would be to change the behavior of
(from the 'skip' link) to automatically save notebook changes much like the 'move' button does?