Re-reading the genteel plays of Mark Ravenhill, I'm struck by his prescience around the moral threat posed by new technology in general and virtual worlds in particular.

In plays like Handbag and Faust is Dead, he's painfully aware that this cyber stuff is going to cause trouble. In fact, the obscene title of his most famous play, Shopping and F***ing, strikes me as a hilarious anticipation of the principal obsessions of the rapidly expanding virtual world of Second Life. The last time I wrote about Second Life its user population was approaching a million people. Checking the website today as I write it has reached 4.6 million, and the number who have been in-world in the last sixty days has risen to 1.6 million. In the last 24 hours these 'residents', as users of the application refer to ourselves, have traded more than $200,000 (£103,000) on Second Life's virtual stock exchange – and bear in mind that this is real money, not game currency.

Second Life, which has garnered a hell of a lot of press, seems to draw extreme reactions as well as just attention. There are a number of well-worn ways to write about it. You can do a breezy walk through of a brief period in the world, and conclude that it's very exciting. You can do an impatient walk through of the world and conclude that it's not for you. Hardcore gamers often have a go, express dismay at the relative crudity of the graphics, and dismiss it out of hand. You can express your utter disgust at the eye of grown-ups playing dress-up in a virtual toy town. You can express greed and excitement at the idea that virtual fortunes can be made here. Or you can amuse your readers with talk of yet more cyber sex on the internet.

What's going on here? Does it matter at all? Quite a few people like to play golf or go hang-gliding, but nobody I listen to is claiming that these pursuits are of any real importance: they're just entertaining leisure activities. If avatars and flying around virtual landscapes and chatting to people dressed as furries isn't your thing, why should you care? And how can you make a judgement without doing hours of research?

Here's a quick way in. If you don't have the time or the inclination to go to the Second Life website and download the application and go through the fairly painful learning experience – and substantial investment of time – to understand what people are doing in these worlds, you can check out the secondary media that is being created around these worlds.

First stop: shopping. It seems that one of the things that people like to do in their Second Life is shop. The website Second Style Fashionista ("Clothes, and hair, and shoes, oh my!") offers female residents of Second Life tips on where to buy the accessories residents use to customise their avatars, or digital representations of their virtuals selves. Male residents looking for fashion types can check out Second Man, to get the latest news on hot designers and pursue "Clothings, skins, and style". The passion and attention with which this community of people is dressing their avatars – choosing the shoes to go with the hat, getting the watch that really goes well with that suit – is a sight to behold.

What does it say about consumption – its eerie immateriality, its fantasy nature – that it can be as satisfying and pleasurable to buy a pair of virtual shoes, such as the Jeepers Creepers rolled-cuff Riggers Boots for your virtual self as it is to buy a pair of 8-hole Doctor Marten boots in the material world? What does it say about where we've got to as a culture that millions of people in the affluent world find satisfaction and delight in this kind of virtual consumption?

It's not just clothes, of course. People are buying houses in Second Life – you can study trends in virtual architecture at a blog like Virtual Suburbia, "The architecture of Second Life, reviewed on the fly" – a knowing reference to the fact that its author, unlike a normal architectural critic, can fly his avatar, like Superman, around the buildings he's checking out. Perhaps you're more interested in vehicles, and will find yourself at Cubey Terra's site, which shows of his collection of aircraft, hovercraft, and submarines, all available for sale at his airfield in Second Life.

As for the second verb in Mark Ravenhill's famous title, here's one resident's explanation of why people are having sex in Second Life. Here's another interesting take. Sexual activity is an area in which people can be notoriously judgemental and close-minded, although I know Times Online readers are an intelligent and worldly community who will think before they leap to judgement on such sensitive matters. Yet again, I would ask the question: what does it say about our culture and our relationship with technology that people not only feel comfortable having virtual sex through digital manipulated versions of themselves, but enthusiastically seek such out experiences? It's clear that in some cases they prefer them to the more dangerous and carbon-based traditional forms of sexual practice.

Second Life is a virtual world whose denizens represent the extreme edge of our confrontation with what it means to surrender the material and move towards a more complete identification with their digital identities. Its most passionate users haven't just started to identify with their e-mail address, they've morphed their sense of identity into something quite different. It's identity play taken to the next level, and I think that it is characteristic of our culture and its obsession with technology. I don't think that we'll all become users of Second Life, but I do think that millions of people are now leading second lives and often secret lives online, in chat rooms, forums, bulletin boards, on website discussion groups, on their blogs, in their IM chats with distant friends, in their e-mail identities, in their gaming lives. Many of these lives are invisible and intensely private.

The interesting thing about Second Life is that it is virtual life made visible, and a lot it would be very familiar to the character's in Ravenhill's play. Go to Snapzilla and see what your neighbours and bosses and relatives are doing, and stare in wonder and confusion at what we've become.

Michael Parsons, now editor of CNET.co.uk, was once European correspondent for The Red Herring magazine, and spent five years working in Silicon Valley and worrying about technology. He can be reached at michael.parsons@cnet.co.uk