I thought they were building some new stuff in Detroit. It turns out it was for the Transformers 4 set that starts shooting on Monday. At a Detroit construction site, Paramount seems to be building a new set. Since Transformers 4 is the only movie I am aware of that is prepping to film in the city, it isn’t a reach to assume its being built for the film.
Right now it is still to early to tell what its final look will be but parts of it seemed designed to be incomplete. It also seems to have a Chinese influence so it might be part of whatever is planned for story points set in China and Hong Kong and tie into whatever is being filmed there towards the end of the production schedule.
Considering the effort being put into strength and support, I guess people will be filming in and possibly on top of it so it has more purpose than just something to be destroyed (even though that could happen too). Check out some of the pics from Jerry B via transformerslive.blogspot.com