If memory serves correctly, the general consensus amongst my peers in the P2P space was that a statement attributed to Scott McNealy — “Privacy is dead, deal with it” — was just a throw-away phrase made by a dumb tech CEO who loved to shoot his mouth off way too much.
The general consensus may have been correct, but McNealy's statement was prescient. When McNealy's line about privacy was still heavily quoted (about 5 or so years ago), instant messaging was still largely the province of early adopter-types, SMS messaging was something that only disgruntled Filipino voters used and 9/11, which brought with it a new wave of bloggers, had not yet happened.
Nowadays, even among “late adopters”, casual conversation appears in electronic forms of all sorts, from email to chat to blog and discussion forum postings. Unlike smail mail, which the police would need a warrant to read, and face-to-face and phone conversations, for which they'd need a warrant and to be at the right place at the right time with a recorder, electronic conversations, as data on the drives of service providers, are easy to record, duplicate and subpoena.
George and I went to university together and each of us has said a number of things we regret (George, maybe a dozen; me, three or four…dozen…). This was back in the late 80's and early 90's, so most of our skeletons live in an offline closet. It's different today, where instant messaging and email are used in addition to face-to-face conversation, the conversational faux pas you make in your callow youthfulness can return to haunt you years later.
Bruce Schneier covers this issue in a Forbes article titled Casual Conversation, R.I.P.. Although he uses U.S. Representative Mark Foley's inappropriate IMs to pages as a launching point for his essay, he makes it clear that Foley is an anomaly and explains why we need some kind of legal privacy protection for our electronic conversations:
Most of us do not send instant messages in order to solicit sex with minors. Law enforcement might have a legitimate need to access Foley’s IMs, e-mails and cellphone calling logs, but that’s why there are warrants supported by probable cause — they help ensure that investigations are properly focused on suspected pedophiles, terrorists and other criminals. We saw this in the recent UK terrorist arrests; focused investigations on suspected terrorists foiled the plot, not broad surveillance of everyone without probable cause.
Without legal privacy protections, the world becomes one giant airport security area, where the slightest joke–or comment made years before–lands you in hot water. The world becomes one giant market-research study, where we are all life-long subjects. The world becomes a police state, where we all are assumed to be Foleys and terrorists in the eyes of the government.
I'll close with my favorite line from the article: “A world without ephemeral conversation is a world without freedom.”