Except that temples are only going to be place holders. As stated, there will be no curses or holy wars. There was no mention of being able to make specific statues/engravings (at least in the last blurb). What was stated was that you can select a deity appropriate to your civilizations. There will also be quality modifiers, from "shrine" to "grand temple" I believe. The only purpose the temple will be to give warm fuzzy feelings to dwarves with devout personalities.
The only cool thing about this (for now) is that civilizations can start worshiping megabeasts if the critter successfully attacked them enough. So you can make a grand temple for "Hakkar, a giant winged serpent made of flesh. Beware his poisonous blood!" In this case, sacrifices become mandatory. At first you can butcher a few pigs here, but to truly stave off the destruction of your fort you will be required to sacrifice sentients on the altar at least once a season. The method for sacrifice is up to you, but it must be as messy (bloody) as possible. No true temple will be complete without a fresh coating of blood splatter applied several times a year. BLOOD FOR THE BLOOD GOD!!!!