As of today, Second Life counts 2,341,910 residents, as defined as "uniquely named avatars with the right to log in to Second Life, trade currency and visit the community pages". Critics make the distinction between registered users and active users, using a 10% conversion rate (confirmed by Linden Labs). This puts the number of Second-Lifers in the 200,000 to 230,000 range only. See CNet article.
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