Have you poked a friend today? Your answer will determine your loyalties in the greatest intergenerational split since the Sex Pistols swore at Bill Grundy on live TV. Friend-poking, along with superpoking, wall-posting and hikkuping – as the clued-in among you could yawningly explain – is simply an internet-enabled social greeting. The rest of us – especially, duh, the dinosaurs still buying newspapers (LOL!!!) – might dismiss Facebook, MySpace and a gazillion other social networking tools as short-term, vacuous fads. But that would be to underestimate a vast shift taking place in how a younger generation is defining its social life and privacy.

What makes Facebook such a tempting multibillion-dollar target for litigation is its compelling ability to tap into the digital generation’s Zeitgeist. For under 25-year-olds in particular, who have grown up blogging, photo-sharing and chat room flaming, today’s digital social networks offer its participants all the status-enhancing tools needed obsessively to shape their public persona. Driven by peer pressure as much as the practical benefits – well, would you want to miss the party invitations? – three-year-old Facebook already claims 31 million active users, with membership growing at about 3 per cent a week. Along with rivals such as MySpace – owned by this paper’s parent corporation – it has become a key enabler of today’s youth-focused culture of virtual self-expression.

Call it Web 2.0 or Me Media, this culture mashes up elements of creativity and raw emotional honesty, of exhibitionism and voyeurism. You risk insignificance unless you are a visible presence 24/7, which explains the relentless noise of personal video broadcasts via kyte TV, of text message “microblogging” via Twitter. As Duncan Watts, Professor of Sociology at Columbia University, explains it, the compulsion serves the vital human need to hang out and be seen. “You’re with your friends, but you’re also creating the possibility that you’ll bump into someone else,” he says – which could mean a date, a real world social invitation or simply another virtual acquaintance.

What the non-networkers tend to find incomprehensible – there are happily Facebooking septuagenarians but the split is largely along age lines – is the casual honesty and alarming openness of these sites’ core under25 participants. Under the new etiquette of social intercourse, strangers may expect to peruse your sexual orientation and home phone number, your education and employment histories as well as your candid photographs. “Facebook may also collect information about you from other sources, such as newspapers, blogs, instant messaging services, and other users of the Facebook service”, declare the terms of service. Yikes. It makes all those warnings about shredding your gas bill to avoid identity theft sound marvellously quaint.

Yet it would be wrong for the IRL crowd – sorry, that means us reactionaries still residing In Real Life – to dismiss these networkers as geekish no-hopers. These tools offer genuine social benefits, from the ability to limit one’s interactions with “friends” one wants only a little contact with, to the opportunity to solicit information efficiently and gain emotional sustenance from likeminded strangers. Immediately after the Virginia Tech massacre, students found intense camaraderie in Facebook and MySpace support groups. And as for engaging this so-called apathetic generation politically, just look at who is out there wanting you to be their friends, from US presidential hopefuls to David Miliband and his YouTube climate-change video homilies. “BS big time”, as one new friend so gracefully replied.

What this generation may not be prepared for is the damaging uses to which its own personal information may one day be put. Just a few days ago, Amy Palumbo, the reigning Miss New Jersey, came under pressure to surrender her crown after indiscreet Facebook photographs of her with her boyfriend – supposedly restricted to “friends” – found their way on to the pages of newspapers. Nor could Chris Dreyfus, a British police inspector with senior counter-terrorism credentials, have expected his Facebook meanderings to prompt a Sun exposé of his “gay lifestyle” (with helpful transcripts of web postings to friends, such as: “Hope the leather shorts didn’t chafe too much on Saturday”). As for students, the group for whom Facebook was originally conceived, they are now finding the grown-ups using their own evidence against them rather too brutally. Poor Alex Hill, a third-year Oxford mathematics and philosophy student was disciplined by the proctors for being “disorderly” on the basis of her postexam celebration Facebook photos. Even poorer Justin Park, a Korean-American student at Johns Hopkins University in Baltimore, was suspended and given 300 hours of community service after the university decreed that his “Hallowe’en in the Hood” party invitation on Facebook, written in a self-mocking gangsta-rap style, violated its “antiharassment policy”. So much for free speech.

And what happens when the teens and students currently disclosing their entire personal lives to LiveJournal, Facebook, MySpace, Bebo and the rest, want to reinvent themselves as serious job-seeking (and spouse-seeking) grown-ups? It is all very well for David Cameron to dismiss allegations about drug use with the assertion that “everyone is entitled to a private past” – but in future, such “pasts” will most likely be documented permanently on publicly accessible computer servers.

How many of the next generation’s leadership talent will decide against a career in public life because, even as you read this, a “friend” is uploading what looks like a photo of them inhaling? No wonder employers are increasingly admitting to using job applicants’ online histories as a means of vetting them. As for prospective future health insurers or lovers: take a stroll through sites such as Jaiku and 43Things to discover that Nikola N “has just had an HIV test”, or that another woman, identified clearly by her photograph, plans to “go to rehab, get my son back and stop using [crystal] meth”.

Remember, we are still in the early days of this uncharted revolution. Wait until your best mates all start “lifecasting” their video thoughts live throughout the day. Already start-ups such as Ustream and kyte TV are offering band width for “your own TV channel” that allows you ubiquitous interaction. Nor is being too busy to update your online output any longer a valid excuse. For a fee of £369, you can now hire a stand-in to be your “digital biographer”, who will “enhance” your online presence based on a detailed briefing with you over Skype.

Some day, many of this hyperconnected generation may regret their abandonment of personal privacy. But, as they are doubtless twittering and IMing and vlogging in response even as you read this, who cares what the MSM – the mainstream media – think? There are too many friends at the wall waiting for a return poke.

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