MySpace will open up its data portability project broadly on Thursday, after launching it with a handpicked set of partners last month.

The project, which the company calls the MySpace Data Availability Initiative, will become publicly available so that any Web site can participate. On Thursday, MySpace expects to release the data APIs (application programming interfaces) and publish documentation on its developer site.

MySpace launched the initiative in May, backed by partners Yahoo, eBay, Twitter and fellow News Corp. unit Photobucket.

The initiative's goal is to let MySpace members share their public profile data outside of the walls of the social-networking site. With this project, MySpace joins a number of Internet companies and industry groups in their pursuit of a data portability solution.

Along with social-networking sites' rise in popularity, a problem has emerged: people who set up accounts in multiple social networks have to re-enter all their profile information in each one, and then manually update it. The goal of data portability is to automate this data entry and updating task and to give people control over the information, photos, videos, comments, friend contact lists and the like that they enter into these sites.

At MySpace's Data Availability announcement in May, its CEO and co-founder Chris DeWolfe said: "Your personal online social profile will become your Internet address. Social activity isn't about creating a walled garden. Socially dynamic Web destinations should be portable and allow users to import and export aspects of their platform."

While the goal of data portability is generally welcomed, its implementation is a complicated matter, involving all sorts of technical, legal, regulatory, privacy and security challenges. In the meantime, companies like MySpace are taking the first steps in what will be a long process to achieve full, industry-wide data portability.

For now, the MySpace effort is designed to let its members carry to other sites their public basic profile information, like their bios, interests, favorite music and movies, as well as their photos and videos. Changes made to these elements on their MySpace profiles will be dynamically updated on the third-party sites.

Users will also be able to decide to drop a site from their network of updates, which is key to privacy and security principles. MySpace members will have a control panel where they'll be able to manage their "data availability" parameters. That control panel will also go live on Thursday, said MySpace Senior Vice President of Technology Jim Benedetto in an interview.

Eventually, MySpace would like to extend the effort to allow members to bring in data and content that they have entered into other sites, making the exchange bidirectional.The project's founding partners haven't yet enabled the data availability functionality on their Web sites, because each one is working on deep, sophisticated implementations, Benedetto said. However, the wide release of APIs on Thursday should lead to some quick implementations by smaller "mom and pop" Web sites, he said.

MySpace members will know that a Web site is participating in the data export program because the site will display a notice to that effect, Benedetto said.

Yet, MySpace members will manage their data sharing with the external sites from their MySpace data availability console. That's because the system has been designed in such a way that the participating sites don't store or cache any of the members' data, which remains at all times in MySpace servers, Benedetto said. This allows members to cut off the data export to any site on a moment's notice in a way that assures them their data remains within their complete control, he said.

Other data portability initiatives include Google's Friend Connect, Facebook's Connect and the Data Portability Workgroup.