I see 5 right now but it's very likely there are more.
4 of them are seen here:
1. wreath against Gingerbread Window wall (see screenshot)
2. wreath against Gingerbread Arch's left half (see screenshot) (it's possible this is true for the Gingerbread Wall & Fancy as well)
3. Snowdragon vs Castle Gate (see screenshot) - sorry but it looks very phallic now:o same for Snowcat, trees... (the wall is always on top)
4. same as 3. but against Castle Wall
Fort layering will appear as it does when you enter your own fort (or view someone else's for attacking). There will be no surprise tweaks: as I believe I have said in the news thread, what you see is what you get (sans damage) which many people who have declared their forts "finished" days ago are relying on.