Facebook will announce its 500 millionth user any day now, and that's around 22% of all internet users globally. That's a pretty impressive milestone, but founder Mark Zuckerberg has already said he expects Facebook to reach one billion users before long.

But given that take-up among those key demographics in the developed world isn't far from saturation, the next phase of growth will be in developing markets and will prove harder work for the firm in the face of domestic incumbents, technological differences and government censorship. So how is Facebook moving in on those markets?

• Venturebeat interviewed Facebook's head of international growth, Javier Olivan - the guy who led Facebook's crowdsourced translation project. He described the development of a free, low-bandwidth mobile version. Facebook is making deals with at least 50 operators across India, Russia and more that means the expense of using data services is carried by the operators rather than users.





Photo by orphum on Flickr. Some rights reserved

• Across Asia, the growth pattern varies from one extreme to another. Indonesia is just 500,000 users behind the UK, Facebook's biggest userbase, and is top, according to comScore, in the Philippines, Singapore and Malaysia. But in Vietnam and China Facebook is blocked, and elsewhere, like Russia, it faces an uphill struggle to overtake domestic rivals.

• Facebook acquired a Malaysian contact importing service called Octazen Solutions, which means it can tap a wide range of email services in the region.

• In India, the site built a database of school details to pre-populate lists and make it easier for users to search for friends, one of a number of 'under the hood' strategies for growth.

• Facebook is closing in on Google's Orkut in both India, which appears to be stalling, and Brazil, where it has a quarter of Orkut's traffic.

• In Japan, where it has 5% of the traffic of market-leading Mixi, Facebook had to focus on making a decent mobile web version rather than replying on apps. In Japan and South Korea, more users access social networks via mobile than by desktop, so Facebook has some substantial catching up to do given that Olivan admits its mobile site was "unusable" eight months ago.

• Interestingly China appears a no-go area, with Google's problems and eventual withdrawal, the current block on Facebook and the dominance of domestic sites like RenRen, 51 and Kaixin001 presenting too much of a challenge at this stage. Olivan puts this down to "an ROI calculation that goes into every country we consider entering".

• The New York Times also points out that though Olivan only has a team of 12, he is backed by Facebook's $1bn annual revenues, which means significant investment in new products and a steamrolling of its rivals. It also means Facebook can continue to hire much of the world's best developer talent, which it regularly poaches from Google.

Will Facebook reach 1 billion? I don't doubt it. We can expect them to focus on the highest growth countries with strong commercial potential and the least established incumbents. But this will still be like Bagneres-de-Luchon to Pau on stage 16 of the Tour de France. Tough, in other words.

Also in Facebookland

• The New York Times has helpfully compiled an introductory guide, for those who might have been living in a cave for the past four years. Or, my mother.

• A Futurescape report predicts Facebook will fight Twitter for the $180bn global TV ad market as these social networks and back channels are formally built into new TVs. While social media has some impact on TV ratings now, the report predicts recommendation, discovery and content sharing will be central to pay-TV services in the future.