Don't forget the fact that the book, even in paperback, is big enough to severely wound somebody if you throw it at their head. And something like a third of its bulk is footnotes. Lengthy footnotes that can be fill most of a page. There is a certain joy to making your way through a dense labyrinth of a story like this, but you have to put a lot of energy into the journey...

Okay, now I'm definitely sold. I'm a sucker for footnotes in a story.

For footnotes, have to mention House of Leaves (Danielewski) as well, although this definitely falls more into the gimmicky "hold the book up to the mirror" camp than the eloquence of IJ.