“Last week the next phase in the theatrical viewing experience took a significant leap forward, as Steven Spielberg and Peter Jackson signed on to direct and produce for Paramount’s DreamWorks Studios a trilogy of 3-D movies about the intrepid Belgian comic-book hero Tintin. And on Saturday nearly an hour of footage from the 3-D concert film of the Irish rock band U2 made its debut at the Cannes Film Festival.” So is 3-D the future of moviegoing? Some major players would like it to be.