One thing I really like in this edition is that the terrain pieces are given rules for them. They are not a point cost to a player, but they are just pieces of terrain that have more specific rules, and can lead to some more interesting missions. Here are some of the new rules for more terrain pieces.
Please remember that these are still considered rumors. The official release is only hours out now, when we can start discussing the book in detail.
via an anonymous source on Faeit 212
Along with the Manufactorum and Shrine of the Aquila there's a couple other terrain dataslates in the book including:
-Basilica Administratum (4+ cover, Can re-roll Mysterious Objective results)
-Sanctum Imperialis (4+ cover, units inside get Adamantium Will and Night Vision)
-Battlescape (Just a 5+ cover and dangerous terrain.)
-Wrecked Imperial (Aquila) Lander (Mysterious Wreckage: D6 Roll, 1: Unstable Fuel Core - D6 S5 AP- hits on the unit. 2-4: Nothing happens. 5-6: Archaeotech Cargo: Place an objective with 3" of the lander if the game uses victory points, at the end of the game, whoever controls the objective gains an additional VP. (Guess this means this kit might come back?))
-Twisted Copse (5+ cover, no additional rules.)
-Moonscape (6+ cover but +2 Go To Ground save instead of 1.)
There is a section that encourages scratchbuilt terrain and you would make dataslates for them based on the dataslates in the rule book. These however, are a consensual option with your opponent. (House rules.) However, it appears that they want you to make the terrain kits fairly close to the examples set out on the box. Nothing you couldn't hammer out with a good opponent.