Linden Lab will build a fence around adult content in Second Life, creating dedicated adults-only areas in the virtual world and banning adult content from appearing anywhere else on the public grid, the company said Thursday.

Users -- known as "residents" in Second Life jargon -- who want to visit the new red-light districts will need to verify their age, according to a statement on the Second Life Blog. Residents hosting adult content on their areas of Second Life will be required to flag that content. Search results will be filtered so that people who don't want to see adult results won't have to see it.

"We're doing this to make content people want to see more easily available to them, and content people don't want to see not as easily available to them," said Linden Lab general counsel Marty Roberts. "As the number of users in Second Life has grown, the call for this has grown. We have more kinds of people in-world, and some of them want to have a more predictable experience than we've had in the past." In particular, Second Life is becoming more popular with educators, who want to be able to predict that students won't stumble over content they don't want to see, Roberts said.

Linden Lab is not trying to wipe out adult content in Second Life, Roberts said. "Definitely not. We're just trying to make the experience of the vast majority of people more predictable."

Linden Lab is seeking input from residents over the next six weeks to help refine the policies -- including coming up with a definition of "adult" content. The company also is still figuring out how to implement age verification -- it might use a credit card, validation by its third-party Aristotle age verification provider, or some other method.

Linden Lab plans to implement the changes in early summer, and residents will most likely have 60 days after that to conform to the new rules, Roberts said.

The changes mainly apply to the so-called "Mainland," a virtual continent in Second Life containing most of the virtual "land." Linden Lab plans to create a new continent for adults-only content (Second Life blogger Dusan Writer dubbed the new continent "SLamsterdam"), with the existing mainland restricted to more family-friendly fare.

Businesses and communities on private servers, known as "islands" in Second Life jargon, will not be required to move, although they will be required to flag their content if it's adult-oriented. Residents with private homes in Second Life will probably be able to engage in adult activity, even on the nonadult mainland, so long as they keep those activities private, Roberts said.

"We haven't mapped out every possible scenario, but if it's in a private home, and it's not visible to passers-by, and you don't advertise it, then you probably won't have to move," he said. "Think about it in real life. If you're walking down the street and you can't see into the private home, it's fine."

The change could be a hassle for larger adult businesses on the mainland, with complicated virtual buildings, furniture, and landscaping, which will need to move all that to the new adult continent or a private island if they want to remain in business. "We're going to roll out some programs to make the transition period as easy as we possibly can," Roberts said.

Linden Lab already distinguishes between Mature and PG content. PG regions are designed to be free of sexually explicit language or behavior, swearing and other forms of aggressive language, and violent behavior and imagery, including horror. Mature regions allow that material, although "explicit adult content must be contained behind 'closed doors,' " the policy says. Adult content is now defined as representations of explicit conduct or genitalia, intense violence, photo-realistic nudity, and sexually themed spaces.

Second Life has largely failed to live up to the hype it received in 2006-2007, when Linden Lab and its boosters predicted it would be bigger than the Internet, and BusinessWeek put the Second Life business Anshe Chung on its cover, promising readers real-life riches in the virtual world. Despite the hype, Second Life remains a niche activity with a regular user base measured in the hundreds of thousands worldwide.

But neither is Second Life failing, as some blog critics, such as Fast Company, take for granted. "Our concurrency is the highest it's ever been, we have more new users than ever, the total usage hours of all residents during the month is at its highest ever. We think all of these are indicators that we're definitely not dead," Roberts said.

Total user hours was up almost 25% Sept. 1 through Feb. 22; user-to-user transactions have grown 30% in the same period, to $37 million in February; and peak concurrency is now over 85,000, Linden Lab says.

Another myth about Second Life: It's all about the sex. In fact, while cybersex is popular in Second Life, it accounts for about 3% to 5% of content on the mainland, Roberts said. InformationWeek did an in-depth report on sex in Second Life in May 2007.

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