I think we can all hope that they don't decide to add TOO much dialog. The problem with video games is that stories are nice, but they need to compete with gameplay, and if more is put into dialog rather than gameplay, the game becomes something that no one wants to play
Shadow of the Colossus is a game that went more for the gameplay aspect rather than story, the story, however, was told through the gameplay, and while barely talked about, was the driving point behind the motives (well, the Wander's, ours was stabbing glowing spots on giant rock/grass monsters)
Silent Hill 2, negitive to SotC, focused on the story and setting rather than gameplay. As Yahtzee said, "it's good at telling a story without words." The combat was difficult and frantic, along with the 3rd person fixed cameras. But it told the story well, and was compelling and you wanted to know what happened next.
Heavy Rain also went for the story. But it might have found a way to keep the story and gameplay on par, sure the gameplay is nothing but quicktime events, but in this sense, it accents the story well. I find myself worried about the characters, teary eyed and nervous and my heart pounding hard just like any character.