Well, if you want suggestions, there's one on my mind that I do for campaign worlds I whip up.
" 'Everyman' Knowledge "
In short, it's what a majority of the populace "knows" as truth. Even if it may not be so. It typically first serves as a quick summary of differences between game world setup and real world, such as..
Number of days in the week / month / year, and the names of those involved.
Number and names of moons, at least via the "majority" common race / language.
The most prevailing races, nicknames of, and some common (mis)conceptions about them.
Likewise, the same for some of the monsters. That's where it gets fun to really throw in myth-bits, such as if people believe trolls will turn to stone on seeing the sun, or such'n'such critter can steal your soul if it kisses you. That sort of thing.
Then a few locational bits, like 'The best ale's in the land come from Suddgart', or how nearly everyone has heard of the Silver Gryphon mercenary company, renowned for tackling the worst battles and winning.
This sort of thing, when trimmed down to two pages or so, and handed out, gives a great foundation for people new to a game, but not wanting to read page after page after page about it and -trying- not to know more than they should. It also is good to get people more interested in actually reading up on the history and locations, I've found.
Furthermore, I would think it'd make it easier to delve into the rest of the bookstuff if they already have a quick footing on how days and such are handled, what the moons and -basic- importance of them are. At a glance info, before the hefty, just seems to let my players absorb information better.
Now, with shadow worlds diversity, you might need purely locational based 'Everyman knowledge'.. But if your doing notes on major areas so far, that could tie nicely to them. I -don't- think anyone would want it as a full page, in the middle of the book, starting a chapter (except, perhaps me). Aesthetically, it'd probably go better as some side-bar setup, or handouts to copy in the back.
But that's my thought on it. No stats, no guarantee of truth. Just something to help get the mood and thoughts set quickly.
- Shirra Whitefur