One thing I have been saying for at least a decade (in more depth; I'll keep this short) is that technology makes reality fungible. In particular, your reality can be different from my reality.
Of course, we all always bring our own bias, experience, and self to the interpretation of every event; my wife sees Shakespeare very differently than I do. And in the current day, almost everyone spends time looking for information that reinforces their own preexisting world view -- hence the political blogosphere. But, up through the era of the three major television networks, TV was a shared experience: you could talk on Friday about that Thursday evening episode of "Little House on the Prairie".
But, starting more than a decade ago, it became possible for broadcasters to modify your visual experience so that it didn't directly correspond to, for example, the reality that a baseball fan saw at the stadium. It started with "ad inserts" into the background, behind the batter. At first, they were all the same for a given network, but there's no reason at all that they can't be different for different viewers -- and, indeed, I believe that the inserts that Japanese broadcasters put into Major League baseball games are different from what the U.S. broadcasters insert.
Carried to its extreme, almost anybody anywhere in the chain can modify the viewing experience of the end user, on an individual basis. In fact, I think TiVo did this years ago -- selling personal demographic information, or at least promising to show the Cadillac ad to wealthy viewers and the Jeep ad to sportsmen. Thus, TV is no longer a shared experience.
For data carried over IP networks, it's even more trivial. Any web cache or network box can, in theory, modify your personal experience of the web (or any other form of data carried over the Internet, as long as it's not encrypted). And now, via Lauren Weinsein's blog, we find out that Google is no longer a shared experience.
Of course, in one important sense, Google never was; they can (and do, I believe) modify search results to be personally relevant. The difference in this case is that the reality funger is not someone you planned to trust (Google), but someone you didn't (Rogers Telecom).
Twenty-odd years ago, it caused a stir when National Geographic magazine digitally moved one of the pyramids, and the movie "Clue" was considered clever because it had different endings in different theaters. Now, it's within the realm of possibility for someone with enough processing power and the right position in the network to tailor the results of a ball game -- I see the Red Sox win, you see the Yankees win.
What happens when political censors in some authoritarian country get ahold of this technology? Election results, indeed, most of reality, can change. Reality, or at least its perception, has become fungible, "reality-based community" be damned.
Or will Feynman be right in the end?