Here's an interview with Solomon. Not much new, but:
His conversation with Julian Gollop sounds kinda like it consisted of something like "Hey, I'm working on a game based on your game!" "Oh. That's nice.".
Wall and scenery objects can be destroyed, floors and ceilings can't, and won't collapse.
Return of the floating roofs? "It’s essentially the same as the original game.", he says. "It's a step back from Apocalypse", I can't help thinking. Heck, we could even blow holes in floors and ceilings in the original game, and it was many peoples' favoured tactic for dealing with big UFOs. Wat.
Also, out of the five or so things he lists as a hindrance to having TUs, the only one that actually looks like it'd be problematic in any way is, as usual, the perks system, and we've already discussed ways to make that work with TUs, elsewhere.