Technology commentator Bill Thompson has been betraying confidences on his weblog. And he is not alone.
One click and the world can read your thoughts online
This week I was at an invitation-only event organised by the Judge Business School in Cambridge.
During the evening session about the future of the media, I made lots of notes on my laptop.
I suspect that the tapping away irritated the person sitting behind me, but it is the best way I have found to make sure I pay proper attention, and I tried to type quietly.
Afterwards I went home, tidied up the resulting 2,500 words of text and posted them on my personal weblog.
I took out the comments that I thought might be too revealing, cleaned up most of the spelling, cut the boring stuff, added some relevant links and hit publish.
It is the sort of thing I do quite often, partly because once I have written the notes, it seems a shame not to share them and partly because I like to contribute to the ongoing public conversations around subjects that interest me, like e-democracy, the future of the internet or the politics of the wired world.
In this case the distinguished panel was discussing the future of the media industry, and all three of them had a lot of interesting things to say.
I was there to speak about blogging, and the challenge it poses to the practice of journalism and the profitability of media corporations, so it seemed like a good idea to blog their debate to show them how it all works.
Unfortunately the organisers had forgotten to tell us that our meeting was held under the Chatham House Rule.
This is a convention, named for the London headquarters of the prestigious Royal Institute of International Affairs, that means everything said is non-attributable.
Nobody writing or talking about what was discussed is supposed to say who said what, nor the identity of who was there.
It is somewhere between a private, off-the-record meeting and a public event, and is generally very useful because it means that people are encouraged to speak frankly without worrying that their words will be in all of the papers or the net the following morning.
Of course, it is an honour code and the only real sanction on anyone who breaks it is that they do not get invited to those sorts of meetings in future.
This is just as well because I had broken it, and by the time I realised it was rather too late to do anything about it - my blog entry was out there, being indexed and cached and linked to.
I think I have been forgiven, and being the token blogger meant that I could use it to make a useful point to the assembled experts, because my indiscretion made it very clear that in a blogged world just calling something private is no longer enough.
It only takes one person who does not realise or who decides that the rule makes no sense and the details can leak out.
You do not even need to know the phone number of a friendly journalist any more. A Blogger account will do just fine.
Of course, some still attempt to control what is said. Google, home of all the world's information, famously insists on a no-blogging rule for its invitation-only Google Zeitgeist events.
This seems to stick because those invited are either loyal to the company or so keen on retaining their exclusive status that they decide to follow along.
In the past we might be indiscreet with other people's secrets, but even if we told a few friends, it would not matter too much.
Now the global conversation that is currently taking place in and on the millions of blogs is increasingly well-indexed and cross-linked.
Mention someone and they may well notice within hours thanks to Technorati or Delicious. Cross-link to another post and you become part of the fabric of the blogosphere.
And once your material is out and cached by Google or simply referenced and copied on other blogs, then it is hard work indeed to remove it from the public sphere.
Slip of the keyboard
Those who would like to control the free flow of information, whether they are organising invitation-only events or running the government in a closed society, need to realise the significance of this change.
The blogosphere has shifted the boundary between private and public, and made it much, much easier for anyone who desires it to engage in the public sphere.
If I had been acting maliciously then I could, of course, have set up a new Gmail account, created a Blogger identity using it and then posted my report anonymously.
I suspect that this would not have worked since I was the only person with a laptop in the room, but normally it would have been effective.
Our normal assumptions about what is and is not public, or about the proper limits on how widely we should share the things we see or hear or learn, no longer apply, but we have yet to figure out a new set of norms.
We need to do something about this, and fast, because otherwise we'll see more slips of the keyboard like the one I made.
Bill Thompson is a regular commentator on the BBC World Service programme Go Digital