Second Life's killer app? How about Linden Lab's killer app?

Some say the Second Life 'killer app' is meetings, some say weak-ties, some say it's art, creativity, live music and other related forms of content publishing, and some consider it to be as simple as the micro-transaction economy, where sums smaller than most payment organizations are willing to handle can be exchanged for both virtual and non-virtual goods, as well as services.

That would be from the consumer end. From Linden Lab's perspective, the 'killer app' for them is closer to what Blizzard's killer app is for World of Warcraft: Your friends and your inventory.

Your friends, many of whom you may have never physically met – and may never actually meet – are available through Second Life, because whatever else you and they may or may not have in common, you have Second Life in common. It doesn't matter that what holds them to it may not be what holds you to it. You're all there, it's where you met, and it may well be the only point of continuous contact.

Quite a number of people have suggested that World of Warcraft leases your friends to you for $15 each month. Sure you may well have alternative contact information for other users, but if you've been through an MMOG closure in the past, you're probably aware that many friendships don't survive the closure of the platform. People just don't tend to keep in touch once that binding platform is taken away.

Second Life owns your Second Life friendships. Not all of them to be sure, but a lot of them certainly. Yank the tablecloth away, and very little will remain on the table. For Linden Lab, that's a huge asset that binds people to the platform.

Likewise, whatever art, content, clothing and objects live in your inventory are a part of the platform. They're another thing that binds you there, and while there are third-party tools that allow the transportation of some of them to other compatible platforms, you're likely never going to see a circumstance where Linden Lab produces a first-party tool or service that allows that inventory to go ... well, anywhere.

A critical part of keeping users under the first-party, Second Life umbrella is hanging on to those virtual assets. If you could have them in any compatible virtual world, then there's one less thing keeping you under the Lab's rules in the first-party environment.

And as long as the Lab keeps a tight hold on your friends and your inventory, very few of you are really actually going to move to alternatives for very long.