This seems quite nice.
However, the presentation medium is doing a great disservice to it.
Three aspects are extremely unfortunate:
1. The font, which does improve upon full page load, is still quite fuzzy.
2. Pages weigh in between 14kb and over 1mb! Each page is stored as a separate .swf file, apparently as an image (including the text pages) with almost no compression whatsoever. This causes a delay of several seconds per page flip.
3. It pegs the CPU if the mouse pointer is anywhere within the page. Don't try to read it on a laptop!