An article in The Economist about Second Life, some excerpts I found interesting:

Second Life, as Mr Yellowlees illustrates, is not a game. Admittedly, some residents—there were 747,263 as of late September, and the number is growing by about 20% every month—are there just for fun. They fly over islands, meander through castles and gawk at dragons. But increasing numbers use Second Life for things that are quite serious. They form support groups for cancer survivors. They rehearse responses to earthquakes and terrorist attacks. They build Buddhist retreats and meditate.

Many use it as an enhanced communications medium. (...) Henry Jenkins, a professor of media studies at the Massachusetts Institute of Technology, thinks that Second Life deserves credit as “a world of hypotheticals and thought experiments.” From new approaches to corporate branding to education, Second Life is a petri dish for innovations that may help people in real life. Already, therapists are using Second Life to help autistic children, because it is a safe environment to practice giving signals to others and interpreting the ones coming back. Other organisations are using Second Life for long-distance learning. Overall, says Jaron Lanier, the veteran of virtual-reality experiments, Second Life “unquestionably has the potential to improve life outside.”

It's interesting to see how SL creates affordances for new activities in virtual worlds; as if it was holding the promises of 3D virtual reality created 10 years ago. The article also focuses on user-generated content:

Second Life provides its residents with the equivalent of atoms—small elements of virtual matter called “primitives”—so that they can build things from scratch. (...) Because everything about Second Life is intended to make it an engine of creativity, Linden Lab early on decided that residents should own the intellectual property inherent in their creations. Second Life now allows creators to determine whether the stuff they conceive may be copied, modified or transferred. (...) Second Life's total devotion to what is fashionably called “user-generated content” now places it, unlike other MMORPGs, at the centre of a trend called Web 2.0. (...) “It celebrates individuality,” says Jaron Lanier, who pioneered the concept of “virtual reality” in the 1980s and is now “science adviser” at Linden Lab. And it connects people, he says, because “the act of creation is the act of being social.” (...) The Web 2.0 crowd also extols Second Life for its highly original business model.(...) Linden Lab does not sell advertising; instead it is a virtual property company. It makes money when residents lease property—an island, say—by charging an average of $20 per virtual “acre” per month. (...) Bill Joy, a co-founder of Sun Microsystems and now a prominent venture capitalist. But “I don't see any correlation between that and what it's going to take to be a designer and have a skill set to succeed in the world.” (...) Mr Castronova also cautions against overestimating the depth and breadth of Second Life's economy. Yes, people do create clothes and games and spacecraft in Second Life and then sell them. But most of the big money comes from the virtual equivalent of land speculation, as people lease islands, erect pretty buildings and then rent them to others at a premium.