It used to be hard to dig for information--before we had the web, that is. Even if the information you were digging for was public, finding it was often difficult, laborious, or costly. So we didn't mind, for instance, that a copy of the deed to the house was available to anyone who bothered to walk over to the local Recorder's office, look up the lot number, thumb through the books in the stacks, and expend a nickel a page on the Xerox machine. Few citizens actually visited these offices. So you likely didn't know what your neighbor owed on his property (unless it somehow became your business to know); nor did your neighbor likely know what you owed on your property. This information was public, but it was tucked away in a hard to get corner of a government office.
Finding your neighbor's phone number in the phone book, on the other hand, was much easier than finding out how much they owed on their property. (After all, that's what phone books were used for, back then.) So in a very practical sense, your phone number was more public than the publicly recorded lien on your house. While it was understood that there was no legal basis to consider one piece of public information more public than another, it was also understood that some information was harder to find than other information. The harder it was to find the public information, the less it was apparently public.
Contrast the above with the situation today. Finding out how much the neighbor owes on their property is about as many mouse clicks away as is finding their phone number. In a very real sense, both pieces of information (the amount owed, and the phone number) are equally easy to reach.
As more personal information--some of it public--comes online, and as search technologies improve, I predict, you'll soon be able to type a name into a search engine and instantly receive a synopsis of personal information about the individual[s] with links that drill down to their finances (e.g. home purchase/sale price, and amount owed), blog pages and comments, photo albums, listed phone number, date of birth, resume, and so on. Every word ever written, every link ever created, on the public conversation that is the web will take on added significance as it will be attributable to its author.
Today, there's still plenty of hard-to-find, public (or practically, public) information. In the future, I predict, information will either be easy or impossible to find. The impossible-to-find, will be private information; the easy-to-find will be everything else. So when a piece of private information leaks, the search engines will be able to quickly assimilate and contextualize the information, and attribute it to a person or group of persons. Search engines will be able to do this, no matter how [apparently] tenuous the link between the information morsel and the person[s] attributed to.
The line dividing private from [practically] public information is becoming razor thin: it is the other edge of the search technology sword. Like time and entropy, information has an arrow along the private/public dimension--from private to public (a piece of public information cannot ever be made private again). This has always been so. Only now, thanks to the web, the rate at which information is becoming public is increasing in leaps and bounds. (And the transition states, as it were, from the private to the public end the information spectrum are becoming fewer and fewer, until there will be but 2: private and public.)
It is easy to imagine a dystopia in which we find ourselves imprisoned in the very public image each of us has projected on the web, where past projections are hard to displace, where labels are hard to peel off, where you must blog in order to protect and enhance your personal brand. But wait a minute! Aren't we there already? And is it so bad?
We're well along the way to such a future, I would say--only, the future needn't be so dystopian. I actually welcome this new landscape, where everyone competes on a more or less equal information footing, where what you know and how you know are more important than your access to information. The problem, I suspect, will be that many will have come to expect their relative anonymity today to continue well into the future. That, I'm afraid, would be unrealistic. I cannot expect this blog post to remain forever unattributable to my real name.