This is bullshit, especially since movies like this are distributed electronically now:

While Shane Black’s Iron Man 3 is expected to open domestically on May 3rd, it will first debut in an international release in IMAX theaters in IMAX 3D starting April 25th.

Last summer, many of the blockbuster releases came a week or two before they were available in the United States. Of course, international movie pirates will be torrenting Iron Man 3 to entitled North American nerds for the entire week before the movie comes out here. This seems to be an admission from the Hollywood studios that they're not that concerned about piracy's effect on a film's box office.