I assume you are talking about your local docs. The Arduino install script that downloaded the docs to local machines didn't download the items found only in extended docs I think - this is supposed to be fixed in 0011 with a new download script a user helpfully wrote.
Also some pages have been eliminated or moved. Basically there are two people that work on docs of whom I am one. The final decisions get made by David Mellis and we sometimes disagree about how and where things will be documented, so sometimes docs are around for a awhile and then get moved or eliminated.