Square Enix's announcement came as a surprise to the audiences at the show. But although the news was huge, it was only unveiled in the form of a few lines of text after the presentation of its FFVIIAC trailer. The company hasn't disclosed details on where Advent Children will be showing, and it seems possible that the movie might only be available in a limited selection of theaters.
This is the second major announcement regarding FFVIIAC that Square Enix has made during the month. The company also announced earlier that the movie will once again be shown as this year's 62nd Venice Film Festival, this time in its completed form."
Found on Gamespot, here: http://www.gamespot.com/news/2005/07/30/news_6130093.html
Maybe, just maybe, they might also show it in theaters in the US. But the chances are about one in six billion. -_-;