Two well-known Web sites have completed implementations of MySpace's data portability program, which has also been modified to allow a degree of user data caching and storage by external Web sites and to support the OpenID single sign-on method, MySpace announced Monday.

The moves represent the latest enhancements to the MySpace Data Availability Initiative, launched in May with big-name partners Yahoo, eBay, Twitter and fellow News Corp. unit Photobucket, and opened broadly to any Web site last month.

With this program, MySpace wants to let its members take their public profile data to other Web sites, so that they don't have to re-enter that information manually multiple times. MySpace's Data Availability Initiative is one of several projects from vendors and industry groups that seek to make data portability a reality for end users, Web application developers and site publishers.

The goal: to automate and give end users control over the process of entering and updating social profile information and content like biographical facts, personal interest lists, friend contacts, photos, videos, text comments and so on.

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 have a control panel to manage their "data availability" parameters. 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.

In the meantime, with the new OpenID support announced Monday, MySpace will let its members create a unique URL with which they can log into sites that support this open digital identity framework. That way, members will not have to remember log in information for every site they register on.

In addition, while the founding partners are still working on their implementations, Flixster and Eventful have become the two largest sites to go live with the MySpace initiative. At Flixster and Eventful, MySpace members will be able to automatically replicate and synchronize their profile information and find MySpace friends.

MySpace is also easing restrictions on caching and storage of member data by participating sites. Previously, MySpace didn't allow any local caching or storage of data by these sites, but now has relaxed that position in a way the company feels doesn't compromise member privacy and security, said Jim Benedetto, MySpace's senior vice president of technology, in an interview.

Now, sites will be able to cache MySpace members' data for a 24-hour period, because forcing these sites to continually retrieve data from MySpace servers was proving technically unfeasible, especially for smaller sites, Benedetto said.

In addition, if MySpace members sever the data-sharing link with a third-party site, the members will now get the option to leave a subset of their profile data on that site, as opposed to completely erasing their data from it. This change addresses scenarios where a MySpace member may want to remove a site from the data availability program but not necessarily drop their registration on that site altogether, Benedetto said.

This technical and policy change reflects the reality that while few argue against the data portability concept, its implementation is far from easy, as it involves many complicated technical, legal, regulatory, privacy and security challenges. As MySpace and others push forward with their efforts, it's generally agreed that achieving full, industry-wide data portability will take a long time to materialize.