Despite being nerdy and devoted to technology, I held out for years before getting a mobile phone. The idea of being permanently available to anyone strikes some people as wondrously great, but it filled me with horror. It still does, which is why I don’t necessarily answer mine, especially if I can’t see who the caller is.

Having the day constantly interrupted by various people, none of whom has anything urgent to communicate, is a sort of madness: you can’t relax because you’re liable to be phoned at any time - halfway through lunch, in the throes of Christmas shopping, bang in the middle of bath time.

If you ignore your ringing phone, you get injured-sounding voicemails saying, “Where are you?”, as though you were in the middle of something intensely suspicious, rather than, say, reading a book or buying some bananas. I find this irritating, but it would appear that I am in a minority: my friends glance lovingly at their ringing, buzzing phones every 30 seconds and my older children do that weird thumb-texting thing amazingly fast, like aliens.

Not being a complete grouch - though clearly I am a phone-phobic control freak who wants to hear from my friends only at my own convenience - I rather like Facebook, which seems a more sensible means of staying in touch with, to put it bluntly, people you are fond of but not particularly eager to see in the flesh (there are exceptions, obviously).

You log in if you want to log in, you post a comment if you feel like it and you don’t if you don’t. The problem with Facebook is the “status update” feature, which enables you to jot down what you are up to, however many times a day you like: India is hungry; India is listening to Leonard Cohen; India is just popping out to the shops; India stubbed her toe.

You can see what the issue is: these Pooterish factoids are not interesting, to put it mildly, but people’s self-regard (mine included) is such that posting inanities is somehow irresistible. Nevertheless, the updates have a certain collective charm - sometimes they read like short stories and, ludicrous though it sounds, there is something cosy and comforting about knowing that A is en route to Thailand, B’s whole-meal loaf is failing to rise and C has just doused himself in Kenzo pour Homme.

Facebook has many other features: you can post pictures, play Scrabble, join ridiculous clubs. The website Twitter, on the other hand, is a one-trick pony: all it does is its own version of the status update, or tweet. No games, no groups, no pictures, nothing but a line or two about what a person is up to at the moment.

Twitter is among the fastest-growing websites. Slightly creepily, you can “follow” various celebs’ tweets as well as your friends’, which seems to me not a million miles away from stalking (and to speak volumes about celebs’ neediness. Weird, isn’t it? They moan about the media and the paps, but they volunteer intimate information to strangers, some of whom are journalists: tweeting is how we came to know last week that Jonathan Ross was rather enjoying his suspension from the BBC).

However: limits. A graduate student at New York University has developed a “pregnancy belt”, a stretchy band with embedded electronics and sensors, which the pregnant woman wears around her stomach and which registers her unborn child’s every kick and tweets about each one.

To be fair, Corey Menscher, whose wife, Ellen, is eight months pregnant with the couple’s first child, invented the belt, called the Kickbee, for a class project and intended it for his family’s private use. “I built it for myself and didn’t know there would be such a reaction,” Menscher said. But a reaction there was, both in the United States and Europe; now he is working on a Facebook version of the Kickbee so that pregnant women can update their status with news of every foetal movement. This ought not, technically, to be terribly different from updates saying “X likes cheese” or “Y would like restaurant recommendations in Brussels”, but it nevertheless seems a piece of information too far.

What is this almost pathological compulsion to share facts with acquaintances and strangers? Even your own mother would balk at being told, for the 22nd time that day, that her unborn grandchild had just wriggled: what a former colleague from a decade ago would make of the fact can only be imagined. It is possible to share facts such as these with friends and family privately, via password-protected online photo albums, or video chats, or whatever. What is extraordinary is the way in which people long to share the minutiae of their lives in public, with strangers.

I used to like a bit of confessional writing myself, but I was paid for it (and how old-fashioned, quaint almost, the “confessional column” - such a staple of the 1990s media landscape - seems: it’s become the journalistic equivalent of riding a penny-farthing). That everyone should be churning out versions of it, unpaid and in their own time, strikes me as fascinating. Does it mean we are becoming self-obsessed, but in a good way, in that people now look to their own lives for entertainment and meaning? Or is it reprehensible, indicative of a society crazed with self-importance, where nothing is special or private enough not to be shared with strangers?

Presumably the gigantic success of social networking sites is to do with some previously inchoate longing to belong to a community, the bigger and more global, the better; equally, there are virtues in belonging, or in feeling as if you do, and Facebook, Twitter and their ilk do no harm: they may even do good.

What is new is the sense that nothing exists until you broadcast it; that anything subjective and experienced privately is of little worth. An unborn child’s kick, for instance, used to be a secret, a tiny communication between the mother and her baby; when I was pregnant, I hated people putting their hand on my stomach unasked. I know tweeting foetal movements isn’t the same as being groped by strangers, but it seems to me there is some overlap. We’ve all invaded our own privacy and gone too far to turn back: it’s only a matter of time before someone tweets the prelude to conception, blow by blow.

+ Gordon Brown appears to spend his time writing to X Factor contestants. Last week it was to congratulate the winner, Alexandra Burke, on her “wonderful achievement”. Brown said her cover version of Leonard Cohen’s brilliant Hallelujah was “sure to be an incredibly successful debut single”. The letter was the last in a long line - the PM had, at the last count, written 13 of them.

Spanish-born Ruth Lorenzo got one: “He said, ‘Keep singing in English, girl. You’re doing a great job!’ ” Daniel Evans, a middle-aged sort, also received a motivational note: “Can I say that the next time Simon says that you are only supported by the over-sixties, you can tell him that my wife Sarah and I disagree.” Brown was also alleged to have written to Rhydian Roberts, a finalist last year, following a phone vote scandal, and has piped up about his love of the show during press conferences.

I don’t believe Brown’s blethering about the X Factor is a cynical attempt to make him Just Like Us - I detect the ring of true fandom. What will the PM do with his Saturday nights now the series has ended? I feel panic-stricken myself, what with last night’s Strictly Come Dancing finale and no X Factor, but have soldiered on through the goodness of home karaoke. Perhaps someone could make the Browns’ Christmas and send over a karaoke machine? Brown always looks like a man with hidden shallows.

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