The technology scene has echoes of the post-dotcom exhaustion of 2002 as we wait for mobiles to catch up.

Where have all the social networks gone? Of course, this is exactly the right time to be asking this question. Haven't I noticed that Facebook is now claiming 500 million users, in the manner of Doctor Evil in Mike Myers's Austin Powers movies? Haven't I noticed that Twitter is getting its very own data centre, all the better to spread “unimportant trivia” (Copyright all tabloid papers)?

Well, yes, I have. But my question is actually about the broader subject.

What I'm really asking is where all the new social networks have gone. In the past two years, especially as Twitter has risen over the media horizon like a sunrise, barely a week has passed without a new network culled from the web 2.0 name generator - take a verb ending in -er and remove the “e” - being announced, often with a press release smelling ever so slightly of desperation that another “me-too” product could become the “us-instead” replacement.

To which the response is always: that hardly ever happens. Despite the insistence of web executives everywhere that rivals online are “only a click away”, you actually have to screw up royally to turn a successful service into one that people leave in droves. (So congratulations to the former managers at MySpace and Bebo: you deserve your place in those MBA case studies of the future.)

Look around, though, and sites such as blip.fm haven't taken off. True, services such as FourSquare and Gowalla seem to be on the rise — although people haven't quite grasped the threat that they can pose to users. So we're back at the original questions: where are all the new social networks? I think they're gone. Done, dusted, over. I don't think anyone is going to build a social network from scratch whose only purpose is to connect people. We've got Facebook (personal), LinkedIn (business) and Twitter (SMS-length for mobile).

Today the technology scene has echoes of the post-dotcom boom exhaustion of 2002-4. Then, the ideas which sank on the reefs of too-slow internet connections and too-few internet users had to wait for computers to catch up. Digg in 2004 and Google Maps in 2005 heralded much of the expansion, showing how a mashup of information meant new possibilities, and the whole “Web 2.0” concept began to germinate.

Now we're waiting again for mobiles, and especially smartphones allied to mobile networks, to catch up with what ambitious startup companies want to do. Apple's insistence in 2007 that iPhone users should have unlimited data plans yanked the entire mobile business forward about 10 years, and briefly showed us how everything should be working by 2012. No surprise that in recent months the mobile networks, unable to invest fast enough, have been rowing back on the “unlimited data” commitment, taking us back to 2007.

The next big sites won't be social networks. Of course they'll have social networking built into them; they'll come with an understanding of their importance, just as Facebook and Twitter know that search (an idea Google refined) and breaking news (Yahoo's remaining specialist metier) are de rigueur. Nor will they be existing sites retrofitted to do social networking, despite the efforts of Digg and Spotify.

So what will they be? No idea, I'm afraid. If I knew that, would I be here writing? Hell, no — I'd be off making elevator pitches and vacuuming up venture capital. Which brings us to business models. Facebook makes its money not just by sucking up ad impressions from the rest of the internet, using its remarkably detailed targeting ability; it also gets a cut from virtual transactions using its own virtual currency. LinkedIn, similarly, can precisely target its executive base. Twitter is different again, selling its user-generated content for big money to Google and Microsoft's Bing, as well as experimenting with direct payment for its EarlyBird sales system and “promoted tweets”. The point being that “ad-supported” isn't the only game for startup revenue. The big sites of the future won't necessarily be about ads as a way to make money, and they won't be about social networks. Now, hunker down and wait. Or get out there and build it. — © Guardian Newspapers Limited, 2010

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