Oldfan said:

I think considering that 3D is doing somewhat well out there, ... this was a missed opportunity by the studio to use 3D to create the true curved feel of the Cinerama format. They could have mapped out the "smilebox" type of screen, but in 3D, requiring the viewer to use their 3D glasses.

That is an excellent idea, Oldfan! Long Live 3D!
But let's not stop there. I say, as the Cinerama screen of necessity reduces the movie's size, fill in all that new black space with (for example) ... the Vinterpalatset Cinerama (Stockholm) or some other opulent cinema of your choice, viewing from the seat of your choice:

[16x9 sized example would fill your widescreen TV]