The growth of social networking sites like Facebook and MySpace will peak in 2009 and will have levelled off by 2012. That's according to a new report by Datamonitor, which suggests that the meteoric rise of the social networks will have reached critical mass by that 2009 date. After that there will be no one left to sign up.

The report also suggests that once market saturation has been achieved by the big social networks, most users will get bored of them. Thus, says the report, innovation and a 'two pronged approach' is required in order to keep people hooked and logging into these networks at a steady level.

Facebook to crash land?

"For social networking services, barriers to entry are virtually non-existent, and both competition and innovation are ferocious," says Ri Pierce-Grove, technology analyst at Datamonitor.

"Users have a vast array of options, from Titanic generalists like MySpace and Facebook to tiny individual networks on DIY platforms like Ning. This year revenues from social networking services should reach US $965 million growing to US $2.4 billion by 2012.

"The extraordinary proliferation of online social networks is fueled by real innovation and is substantially changing the way we communicate. However, the hothouse atmosphere of easy capital, media attention, and user curiosity which stimulates creativity will not be sustained indefinitely.

All players therefore must develop a two-pronged strategy in order to survive the extremes of heat and eventual chill which this market will undergo," she said.

Social networking depression?

Facebook currently has around 50 million active users, while MySpace, owned by Rupert Murdoch's News Corp, has over 200 million.

It's not hard to believe that the vast majority of us will eventually lose interest in these social networking sites. The Facebook interest curve has already been witnessed on a large scale. People sign up and for the first few months they log in every day and upload pictures they've taken. Sometimes it's a mistake.

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After a while, Facebookers are logging in two or three times a week instead of every day. Then it's once a week and gradually the pull of pokes, inane status updates and photos of Friday at the pub fails to lure some people back altogether.

And that's when you get millions of unused accounts just sitting there. Abandoned.

Will Facebook be able to innovate in such a way that will keep people interested in the long term? Check back in 2009 and we'll let you know.