In "The New Journalism" Tom Wolfe describes four devices that give realistic novels their immediacy and power. In the 60's journalists began to use these four devices to give their nonfiction the same immediacy and power.
1. Scene by scene construction.
2. Record the dialog in full.
3. Write from a third person point of view.
4. Record the symbolic details of people's status life.
From "The New Journalism", pages 31-32:
...By trial and error, by "instinct" rather than theory, journalists began to discover the devices that gave the realistic novel its unique power, variously known as its "immediacy," its "concrete reality," its "emotional involvement," its "gripping" or "absorbing" quality.
This extraordinary power was derived mainly from just four devices, they discovered. The basic one was scene-by-scene construction, telling the story by moving from scene to scene and resorting as little as possible to sheer historical narrative. Hence the sometimes extraordinary feats of reporting that the new journalists undertook: so that they could actually witness the scenes in other people's lives as they took place--and record the dialog in full, which was device No. 2. Magazine writers learned, like the early novelists, learned by trial and error something that has been demonstrated in academic studies: namely, that realistic dialog involves the reader more completely than any other single device. It also establishes and defines character more quickly and effectively than any other single device. (Dickens has a way of fixing a character in your mind so that you have the feeling he has described every inch of his appearance--only to go back and discover that he actually took care of the physical description in two or three sentences; the rest he has accomplished with dialog.) ...
...the third device was the so-called "third-person point of view" the technique of presenting every scene to the reader through the eyes of a particular character, giving the reader the feeling of being inside the character's mind and experiencing the emotional reality of the scene as he experiences it...
...The fourth device has always been the least understood. This is the recording of everyday gestures, habits, manners, customs, style of furniture, clothing decoration, styles of traveling, eating, keeping house, modes of behaving toward children, servants, superiors, inferiors, peers, plus the various looks, glances, poses, styles of walking and other symbolic details that might exist within a scene. Symbolic of what? Symbolic, generally, of people's status life...