In the past sites like MySpace have locked users into their own site and jealously guarded member's content.

"The walls around the garden are coming down," says MySpace boss Chris DeWolfe.

The deal means that anyone with a MySpace profile can now share content with any web site. That includes things like photos, video, public profile information, friends' lists and text.

MySpace claims their initiative "throws open the doors to traditionally closed networks by putting users in the driver's seat of their data and web identity".

MySpace's DeWolfe is ready to work with Facebook

Chief operating officer Amit Kapur says "This is an unprecedented move to further socialise the web and empower users to control their online content and data."

More relevant

At the moment Yahoo, eBay, Photobucket and Twitter have signed up but Mr DeWolfe says he looks forward to other sites coming on board including "mom and pop" sites and their chief rival, Facebook.

"This project is open to any site out there that wants to work with us. We are happy to work with Facebook if they want to join up with our effort."

Altogether the participating companies claim a total of 150 million users and reach 85 per cent of the internet market in the United States.

The move also offers MySpace the opportunity to extend its reach outside its core members. Recently it has been losing some traction with traffic falling 16% in April from a year ago. Nevertheless the online intelligence company Hitwise says the site accounted for nearly 74% of US visits to social networks.

Under "data availability" MySpace profiles are synched with partnering sites like Yahoo and Twitter. Users who make a change to their MySpace page will find that the accounts linked in will also be altered. The data is dynamic, which means it can be updated constantly.

MySpace stresses that users will have control over what information they share and who they share it with.

"Finding friends to follow is central to Twitter's value as a real-time communication utility," says co-founder Biz Stone. "This project enhances discovery and connectivity making Twitter more relevant and useful."

MySpace takes the lead

Benedetto says MySpace is no longer an island

As well as saving time and hassle it puts MySpace at the centre of the game because it encourages members to store all of their core data at MySpace to begin with.

As the internet becomes more connected and more social, storing content across a plethora of sites doesn't make sense.

"Socially dynamic web destinations should be portable," explained Mr DeWolfe in a telephone conference that included BBC News. "It should allow users to import and export aspects of their platform."

"This is a pioneering new way for the global online community to integrate their social experiences web-wide."

Michael Arrington of TechCrunch believes "By acting first, MySpace takes the lead and has a shot at being the long term winner - meaning lots of people use MySpace as the place to store data and share it out to other applications from there."

" Look for Google to make their next move," he hints.

Openness

All authentication will be handled through OAuth, an open protocol tool, embracing open standards that the company says will allow the implementation to be as non-proprietary as possible.

MySpace has announced that it is also joining the Data Portability Project to demonstrate its continued commitment to openness and open standards.

Yahoo's executive vice president of platforms, Ash Patel, says "Yahoo believes in an open internet that gives users the flexibility to make their web experiences as relevant, social and personalised as they can."

Technology director Jim Benedetto says this proves "MySpace is no longer an independent island of data on the web."

The changes will be rolled out on the site globally in the coming weeks.