Clay Shirky takes on Second Life and has a lot of new arguments he contributes to the discussion:

So here's my question - how many return users are there? We know from the startup screen that the advertised churn of Second Life is over 60% (as I write this, it's 690,800 recent users to 1,901,173 signups, or 63%.) That's not stellar but it's not terrible either. However, their definition of "recently logged in" includes everyone in the last 60 days, even though the industry standard for reporting unique users is 30 days, so we don't actually know what the apples to apples churn rate is.

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Never mind that the cursor is a terrific way to navigate information; never mind that Amazon works precisely because it dispenses with rather than embraces the cyberspace metaphor; never mind that all the "Now you can shop in 3D efforts" like the San Francisco Yellow Pages tanked because 3D is a crappy way to search. The invitation here is to reason about Second Life by analogy, which is simpler than reasoning about it from experience. (Indeed, most of the reporters writing about Second Life seem to have approached it as tourists getting stories about it from natives.)

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Finally, the current mania is largely push-driven. Many of the articles concern "The first person/group/organization in Second Life to do X", where X is something like have a meeting or open a store - it's the kind of stuff you could read off a press release. Unlike Warcraft, where the story is user adoption, here most of the stories are about provider adoption, as with the Reuters office or the IBM meeting or the resident creative agencies. These are things that can be created unilaterally and top-down, catnip to the press, who are generally in the business of covering the world's deciders.

I share much of Clay's skepticism about the Second Life hype. It is been pushed relentlessly by journalists who probably have never seen it from the inside.

Also Second Life can be pretty boring as there is no immediate game idea behind - but of course that is also the strength as plots are being invented in real time and by users so it is superbly scalable.

But I also consider Second Life as a great feat of technology that connects people all around in the world in a surprisingly versatile design (at least the buildings and avatar design) that seems to have too many options to try even for millions of players.

Here is another fact to consider if you live in a non-first world economy (and have no plans of moving away) it might be interesting to search for opportunities in SL. It immediately connects you to a first world economy (alas with many income flaws but that should change as more Americans join). If you acquire the right skills and build your career in second Life it might be an easy and fun way to earn a salary (as long as no earthquake hits).