Quick, name the media outlet where you first learned about the August 6, 2001, terrorism memo.

And while you're working on that, did you see the new scientific evidence that a positive attitude doesn't help fend off cancer, but masturbation does? Yes? Where did you see it?

We all take in a great deal of media every day, so much that it's often hard to remember which outlet said what. In today's turbulent news environment, as soon as a story enters the marketplace, it begins a whole new existence and loses its connection to the original source. Sometimes, it doesn't even arrive as news per se, but as a kind of vibration from the communal media atmosphere.

For instance, odds are you can't remember precisely where you learned the particulars of the Richard Clarke story. Was it a newspaper? An Internet wire story? Live coverage of his testimony? Perhaps you can't recall any of the above and haven't read a page of the man's best-selling book. Yet somehow, you can speak authoritatively about it—with others who also haven't read it.

For most of the 20th century, the news came from a limited array of sources: hometown newspapers, radio broadcasts, a handful of influential magazines, and, in the last half of the century, several national television networks. With such a small media menu, it was easy to keep track of one's news life, to know that this big revelation or that memorable story came from a particular place. You saw it in the morning paper, perhaps, or you heard it right after dinner from Cronkite himself.

In the last 15 years or so, the media universe has exploded. There are TV screens in airports and headlines on cellphones. News is everywhere at once and nowhere in particular. On any given day, there's no single media outlet that you can assume most people will have seen. Even the New York-Washington Establishment, uni-brain that it is, has no required reading or watching. There's really no newspaper of record, no mandatory magazine, certainly no newscast that everybody feels they need to see.

It's increasingly hard even to find individuals with strong preferences (unless they're ideologues, who have nothing but). CNN or MSNBC? Jennings, Brokaw, or Rather? Do you prefer The Washington Post, The New York Times, or The Wall Street Journal? Feeling strongly about such choices has become an eccentric affectation, like wearing a bow tie. Curious people see all of these outlets—now and then, when they have a moment. But that's not how most of us get our news. To save time and trouble, we listen closely to what people in our own circles are talking about, to elevator chatter and small talk at Little League games. This human search engine is more elegant and efficient than the media themselves. It cuts through the fog and locates the stuff we need to know to be current.

Today, the only media outlet that everyone follows is called Did You See? Did you see what happened to those contractors in Iraq? Did you see the new study about television and attention deficit? Did you see what that mother in Texas did to her kids? The verb alone speaks volumes: To "see" a piece of news is not the same as reading, watching, or listening to it. Seeing is more passive and superficial. It doesn't suggest that you sat down with a news article or absorbed a long public-radio piece. It simply says you picked up on something, got the gist of it. In most cases, the gist is all you need.

Did You See is not just a shortcut. It's a way of thinking about this stage in media evolution. New media products that draw the most attention these days tend to be those that serve the needs of a Did You See world. Blogs, those online journals of commentary and links, are all effectively Did You Sees, one person's effort to boil the news of the world down to a handful of salient items. The Drudge Report, with its constantly changing headlines and shock-horror aesthetic, is a Did You See for noir tastes. Google News arranges the latest headlines using mathematical calculations based on which stories are getting the most play worldwide—a kind of Did You See machine.

There's an obvious downside to Did You See: a lack of focus and depth. A culture of people who flitted through life this way, buzzing about the buzz, would be a miserable place to live. True, we all know a few people like that, and sometimes this country seems to be headed decidedly in that direction. But then, the Did You See is only as good as the material we all bring to it, those occasional new items that each of us notices on our own and brings into the conversation. And we're still doing that.

More broadly, there's something encouraging about this shift. Just when the media seem to be at the height of their power, and journalists are fairly bursting with self-importance, the public basically opts out of the game, saying: "You guys do some nice work, but frankly, I just don't have the time."

No great loss, either. It's now possible to absorb many of the leading products of our great media companies, without actually experiencing them. I didn't watch Diane Sawyer's February interview with Mel Gibson about The Passion of the Christ. But thanks to Did You See, I know all about it. When this week's presidential news conference was over, I decided to skip the after-analysis. But I did "see" it later and was glad I hadn't wasted my time.

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