Looking through this book after the PDF was dropped in my downloads. The cover image is sooo cool at full size. As for what's inside... intriguing I think is the best word. There's a few monsters in the back (nothing of the bad SpellJammer stereotype), but what really speaks to me here is the art.
While it's not the Vitruvian style that I miss ever so much from D&D 3.5, the art is indeed rather evocative of things sufficiently alien to ... be alien. Yet things are not so different that players will be unable to identify with what's presented. That's a hard balance to strike when doing science-fantasy, and in my opinion it was well done. :)
As for the literary content: I haven't had enough time with the PDF to read through it all yet. But I am very much attracted to adventuring on / in Golarion's sun, and the entry on Golarion's moon gives me a teensy bit of information on the ancient history of Golarion, something I have been yearning for from the start (I will so buy a 300 page "History of Golarion", hint, hint). These bits are also the right balance between science and fantasy for a fantasy world's immediate cosmology.
Overall, a solid work for me, without veering too far from fantasy roleplaying.
