The announcement Monday that developers can tap into users' Facebook feeds -- with their permission -- to build new types of services will allow users to access updates on other Web sites, as well as new platforms like desktop and mobile applications.

"Now, you'll be able to view your stream and publish information into it from places you never could before -- like your desktop computer or your mobile phone. Your stream will appear just as it does on Facebook.com and maintain the same privacy settings," stated Facebook in a blog post Monday.

Among the first companies to capitalize on the new Facebook Open Stream API is Seesmic, which enables online video messaging, and now offers a desktop app that allows people to interact with their stream as the would on Facebook, but through the desktop instead of a browser. They can also add comments and "likes" to friends' posts.

"The entire stream will be available for developers to remix and create new experiences, and we expect to see developers create many more applications that optimize the real-time Facebook experience for different use cases," wrote Justin Smith, editor of the Inside Facebook blog, Monday.

The latest effort to extend access to Facebook follows last year's launch of Facebook Connect, allowing members to login to third-party sites using their Facebook account, and its recent redesign focused on delivering real-time updates. The move further highlights Facebook's push to compete more directly with Twitter to be the key social platform for instant communications.

There are already hundreds of tools built around the Twitter API including Tweetdeck, which is also among the first desktop apps to integrate Facebook updates alongside the Twitter stream.

Brands are already trying to get a jump on the era of social commerce by operating their own public profiles on Facebook to connect with customers more directly and informally. Michael Lazerow, CEO of Buddy Media, which develops branded apps and helps run marketer's Facebook pages, sees big potential in the social network's new developer APIs.

"Ultimately, this provides brand marketers and media companies many more tools to build engaging experiences for users," he said. As an example, he imagined Virgin America offering passengers a "Facebook button" in their entertainment system that allows users to read their stream and publish updates at 30,000 feet.

"This is bringing Facebook to the user where the user is," he said. "The user no longer needs to be on a computer logging into the Facebook site or on a mobile device that's done a deal with Facebook."

Inside Facebook's Smith emphasized, however, that the move does not automatically give access to all content shared by all of 200 million of Facebook's users worldwide. "Unlike Twitter, where shared information is by default public, on Facebook, shared information is by default, private," he wrote. "This means that many applications which the marketing community is clamoring for -- like the ability to search and access all updates shared by Facebook users -- is not part of this release."

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