Facebook founder and CEO Mark Zuckerberg, seen on October 6. Facebook on Thursday was getting kudos for giving members better control of their information but dinged for letting people be thrown into "groups" without their permission.

Facebook on Thursday was getting kudos for giving members better control of their information but dinged for letting people be thrown into "groups" without their permission.

A day after the world's most popular online social network began letting users form cozy cliques at the website the Internet was abuzz with grumblings by people who found themselves added to groups without being asked.

Well-known technology entrepreneur and blogger Jason Calcanis posted at his website a copy of an email that he sent to Facebook after being "force-joined" to a group called the "North American Man/Boy Love Association" (NAMBLA).

"There is no opt-in," Calcanis complained, noting that he is not -- and has no interest in being -- a NAMBLA member. "I've now been assigned to a group that advocates...well...ummm...You can look it up; it's very bad."

While unveiling the overhauled "Groups" feature on Wednesday, Facebook said people could easily opt-out and that once they did they could not be signed back up without their consent.

Facebook founder Mark Zuckerberg said that, as in the real world, social standards set by friends, family, or other members of groups were expected to control who got admitted.

People can only be added to a group by those designated as "friends" at the social network. In the case of Calcanis, a friend evidently created a NAMBLA group and inducted folks to highlight a problem with the opt-out approach.

"Many social dynamics on Facebook are determined by the people who use it," Facebook spokeswoman Jaime Schopflin said in response to an AFP inquiry.

"If you don't trust someone to look out for you when making these types of decisions on the site, we'd suggest that you shouldn't be friends on Facebook."

Facebook allowed group members to add others to make it simple and along the lines of "tagging" uploaded photos with the names of people pictured, according to Schopflin.

"If you have a friend that is adding you to groups you do not want to belong to, or they are behaving in a way that bothers you, you can tell them to stop doing it, block them or remove them as a friend -- and they will no longer ever have the ability to add you to any group," Schopflin added.

Any member of a group can add friends to the clique, meaning the circle can grow to include people outside an individual's array of Facebook contacts.

"I found myself added to a group without being asked, and that was worrisome," SearchEngineLand.com editor-in-chief Danny Sullivan wrote in a blog post.

"I was pretty aghast this had happened. Groups got it wrong from the beginning by failing to ask if you want to be included," Sullivan said.

Groups was unveiled along with two features that will give people more control of the information they upload to Facebook.

A new service lets people download all pictures, video, comments and other digital information they have uploaded to the social networking service.

A new "dashboard" feature will let Facebook users see and manage what information in their accounts is accessed by third-party applications.

The online rights group Electronic Frontier Foundation (EFF) called the new Facebook features "important steps" toward giving people more power and control when it comes to their information at the social networking service.

"EFF is very pleased with (the) Groups revamp, which we hope will provide users with a powerful new tool for managing their privacy on the Facebook site," EFF attorney Kurt Opsahl wrote in a blog post.

"We greatly appreciate the additional control provided by the newly redesigned Groups feature, which will allow people to more easily share information only with particular subsets of their friends."