Microsoft said on Monday that it will open up the data format behind its Outlook program.

In a blog posting, Microsoft group manager Paul Lorimer said the company is working to publish the specifications behind Outlook’s .pst files.

“Data portability has become an increasing need for our customers and partners as more information is stored and shared in digital formats,” Lorimer wrote. “One scenario that has come up recently is how to further improve platform-independent access to e-mail, calendar, contacts, and other data generated by Microsoft Outlook.”

The move, he said, will “allow developers to read, create, and interoperate with the data in .pst files in server and client scenarios using the programming language and platform of their choice.”

Google is ready to show off its concept for social search while it figures out what to do with Twitter’s fire hose of data.

Last week at the Web 2.0 conference Google’s Marissa Mayer demonstrated the service, which went live as a Google Labs project on Monday. Google Social Search links the concepts of so-called “real-time” search with Google Profiles and custom search results, allowing searchers to find content created by friends or contacts with Google Profiles.

Google Social Search was developed separately without the Twitter deal in mind, said Amit Singal, a Google fellow. The opt-in service provides your Gmail contacts and friends on public social-networking services with the content you’ve linked to your Google Profile, such as blogs, Twitter or Friendfeed accounts, or any number of published material.

That means that if you’ve linked your personal blog to your Google Profile, your contacts will be able to see your blog posts related to a given query directly in their search results pages. Those links will be placed at the bottom of the search results page for now, and searchers will also have the option to refine the search results page with a new “social” link on the left-hand side of the page to focus just on content from your network.

Google Inc has introduced a new feature that will allow consumers to use its Google Voice service without switching to a special phone number, potentially broadening the appeal of the nascent, and controversial, service.

Google said late Monday that new users of its service will be able to have the calls that they don’t answer forwarded to a special Google Voice electronic mailbox, essentially bypassing the voicemail provided by their phone carriers.

Google Voice offers a variety of voicemail management features, including unlimited storage and text transcription of voicemail messages.

The service also allows consumers to make low-priced international calls by routing portions of the call over Google’s infrastructure and the Internet.

Until now, using Google Voice required adopting a special Google phone number. The new feature allows people to retain their existing phone numbers.

Craig Walker, a group product manager for real time communications at Google, said the company will provide users with a special code to enter into their phone which forwards unanswered calls to a Google-maintained voicemailbox.

Walker said the call-forwarding feature did not require striking special deals with the phone carriers.

“Virtually all the carriers already allow this,” said Walker.