The six companies will exchange functionally-similar Contacts APIs so as to create a safe, secure two-way street for users to move their relationships between the respective services, Richards said.

"This partnership with five of the most popular social networks will make it easier, safer, and more secure for people to access their contacts and relationships from more places on the Web. These networks will be adopting the Windows Live Contacts API instead of ‘screen-scraping,' which puts customers at risk for phishing attacks, identity fraud, and spam," he said.

The APIs require an explicit delegation screen from Login.live.com, so the risk of user data getting phished is substantially reduced, Roberts said, noting that Microsoft had also made other investments to ensure that Login.live.com was as secure as possible from phishing and data theft.

Rob Enderle, the principal analyst at the Enderle Group, is upbeat about the move, telling eWEEK that it is classic a Microsoft move. He said it speaks to Microsoft's strength, as its tools are the common technology behind the offerings that allow them to interoperate.

"This is what a platform and tools company should do. It also creates an incentive for these services to use Live Messenger rather than a competing offering or creating their own, and they'd rather not create their own. Microsoft should do more of this kind of thing," he said.