So this is from the IMAX page but now the page has been taken down. Supposedly the Comic-Con posters have an IMAX 3D experience along the bottom of them too, but this is all hidden.
The back story on this is that Warner Brothers wanted all of their tent pole movies to be in 3D but Nolan made sure to stand his ground and kept all of the Batman movies in 2D. Zack Snyder wanted to do the same but it seems he buckled under the pressure. Now a lot of this information could be miss guided, or Warner Brothers told IMAX to wait until Comic-Con to post the information about the IMAX 3D Superman movie.
If I had to I’d put my money on this being legit, but who made the official decision to change it.
[Now this is where I would say this information came from IMAX website and link it to the Man of Steel link, but like I said earlier, it has been taken down.]