1) I'd like to add to what - was it destiny? - said earlier. Not only are interior/terrain maps generally textured and themed very poorly, but terrain maps blend VERY badly with bricks. Placing bricks on slopes is awkward and sometimes generates weird placement errors, and if you do manage to place them they're cut off at weird angles that don't fit with the game.
2) I really, really hope that actual player-placed lights will cause similar dynamic effects. I know my opinion doesn't matter much but I love to build on dark maps with ambient colored lights placed around. At least to me, a lot of the initial positive reaction to this update would be lost without this inclusion. Regardless, I'll continue to support the update (not that it matters). Great step forward and congratz to you two.