- focusing after the shot - different focus by area of the picture
You're presumably thinking of the Lytro.
And I would tend to agree. Right now, it's a gimmick, a toy...but, at some point, it's going to be a game-changer -- a truly radical revolution.
I also think we'll see the lines between cameras for stills and cameras for video blur to a very great extent. When you do photography for stills, you'll hold the button down for however long you might hold it down for a burst shot today, and you'll then pick either the single frame or some sort of composite of frames. That'll particularly be the case when video gets into the thousand-frames-per-second range, because shutter speed will become irrelevant. So will mechanical image stabilization; you (or, rather, software) will simply pick the one frame out of the thousand shot that second with the least motion. Or, more likely, something will do an intelligent analysis of the thousand frames to reconstruct an even higher-resolution and cleaner single composite frame. You'd also have the possibility for recreating the effects of a slow shutter (water turns to fog) or even a second-curtain flash effect with motion blur trailing a sharp subject. That latter will quickly become a cliche for sports photography.
And I think that we'll also tend to see stills with motion. You've seen the idea, I'm sure, in lots of movies, including Harry Potter.
Instead of a single frozen print, it'll be a one- or two-second loop. The subject's head turns towards the camera and smiles; end of loop, followed by the next frame in the slideshow. The flowers and leaves continuously flutter in the breeze. The batter swings and hits -- presumably in slow motion. The same wave keeps crashing over and over again against the surf. That sort of thing. These will be mounted in picture frames just like any other photograph you might see today mounted in a picture frame, except they'll be some sort of digital display, maybe backlit, maybe not. Again, we already have these sorts of things, but, like the Lytro, they tend to be gimmicky. That will change.
We're also not that far away from the whole-wall-as-a-TV of Fahrenheit 451. When that day comes, expect it to be on all the time, even when people aren't watching a program; it'll instead have a "screen saver" and will be another primary medium for display of photography.