Google+ Gets Shared Circles as Membership Rockets

Google+, which opened to public beta one week ago today, has gotten shared circles, one of the social network's most heavily requested features.

Google+ launched to open beta Sept. 20, expanding from limited field test to let anybody join the network that would challenge Facebook. Google (NASDAQ:GOOG) also added the ability for users to search Google+ for people and posts, as well as the Web. The company also added several improvements to its Hangouts group video conferencing application.

Now users can share their Circles, the groups of friends, colleagues and other contacts users create manually, simply by clicking two buttons. For example, a user who tends a Circle of Harry Potter fans can click on that Circle from their Circles page and click "share."

Users may choose to add a comment to the shared Circle post explaining what the Circle is all about and why they chose to share it. The cool part is that Google+ users connected to the user doing the sharing can then pick and choose who to add to new or existing circles.

When users share a Circle, they're only sharing members in the Circle as of the time it's shared. Users added after a Circle has been shared will not be included, unless of course a user opts to share the Circle again.

Moreover, noted Google+ engineer Owen Prater, users are only sharing its members at that time. Also, the circle name is always private to the person who share it, and any changes they make afterwards are kept private as well.

"We hope this new feature helps you share and find lots of great content in Google+, while still giving you important controls over how you read and share," Prater said on Google+, where he provides a demo video of shared Circles.

The new feature should be a hit among the more social Google+ users, but not so much more private folks. It also comes as Google+ membership is fairly exploding. Ancestry.com Founder Paul Allen estimated late last week that Google+ might have over 43 million users.

Meanwhile, HitWise crunched some numbers after Google+ went public and said the Website saw "a massive spike in market share of visits for the site, with a 1269 percent growth from the week ending September 17th to the week of September 24th." The site also received nearly 15 million total U.S. visits last week.