Google’s link with MySpace.com could provide the biggest boost yet to the media industry’s quest to make money from the online social networking phenomenon.

The alliance announced this week between the search company and the fast-growing internet phenomenon at the heart of Rupert Murdoch’s online strategy – and Google’s willingness to hand over at least $900m of revenue as part of the deal – is another sign of the potential value of social networks and their user-generated content. But so far nobody has devised a profitable business model for them.