Ever read all the books in Morrowind or http://www.imperial-library.info/content/elder-scrolls-iv-oblivion? The sheer volume is astounding. I imagine for Skyrim the same books will be recycled again with new ones added in the mix, giving us probably thousands of pages to read.
The idea of the Library of Tes F'rum is to collect together books written by forum members between now and release. They can be two-page short stories, fictional almanacs, archaic herbalist guides... Whatever you can think of. Come release, a team of people will convert the collection into in-game books, build a grandiose library to house them in, and release it as a mod.
Who's interested?
For now, if you wish to submit a book PM it to me and I will collect them together. Once a decent number start coming in we'll find a better way to organise them.