The PDF of the Pact Worlds Coursebook is very high on my List of Things to Buy Right Now. The world-building is, to me, the very best part of the Starfinder line, so this supplement should be really helpful. So I have a couple of quick questions for those who already have it.
How much space do they devote to Absalom Station? The "Crossroads of the Universe" is important enough to deserve a book all its own, but it looks like it may be in this book. Every player-character probably goes to Absalom at some point, and in some capacity. I've had all kinds of questions in mind about how things work there, what living conditions are like, etc. Some of them I have discussed here, at sometimes alarming length. How many of my assumptions are correct?
Triaxis and Eox look like they will be important once I get a campaign going -- Triaxis for the influential Dragons and Eox for the Grateful Undead, some of whom make unlife look cool without even being human-looking. This should also answer the question that is on my mind, which is whether Eoxian undead retain enough of their original identities to be considered self-directed? If that is the case, then killing one is like killing a living person and will be dealt with accordingly!
The Disp will also be important in my campaign, because it is where Bellantrix the Silver Dragon lives most of the time. Which means PCs will frequently need to deal with their perils.
Looks like I have a pretty long list of things I want thiws book to tell me!
Absalom Station = 10 pages. In fact, that's a pattern for all of the "worlds" sections, which are the first 147 pages. 148-164 expand on starships, 164-179 are a variety of factions and NPC stat blocks (hellknights, street gangs etc.), and 180-214 are player options, including a smattering of additional player races.
I suspect that a lot of what you're looking for will be covered in this book.
The book really does have something for everyone. You aren't getting level by level maps of the station but it's very useful gouge. And the new races, themes and archetypes! I will probably be using the pact world options over the core book for most characters (tempered pilgrim and xenoarchaeologists, oh boy!)
As Serisan said, each of the Pact Worlds gets 10 pages in the book. However, 1 of these is for a full page map of the world/station/lunar system; 1 of these pages is for a new Theme tangentially related to that 'world' and there's roughly another 2 pages (maybe three, depending on layout) of art. It's probably only about 5-6 pages of lore and some of it isn't new, if you've already gotten the APs for the places that have gazetteers in the APs (including Absalom Station in Dead Suns 1).
Now, to be clear. The Maps, the Themes, and the art are all well worth the pages they're printed on. They're some of my favorite content in the book. I don't want any of the above to be mis-construed as a complaint. I just want to manage expectations, effectively, so no one is disappointed (you shouldn't be, the book is, IMO awesome). I really love the detail of the lore provided on all the worlds I've read so far (I'm up to Verces).
Eoxian undead are definitely 'people' both in the philosophical and legal senses.
A lot of questions are answered in this book. Better though, every page is dripping with plot hooks and interesting places for anyone running or playing the game. It actually gives you a lot more questions, and that's part of the fun of running a game like this.