Counting registered users instead of daily active users tells us nothing about the popularity of the service. Think of the millions of people who’ve registered for Google+ but never use it. Second, given the huge popularity of Google search, Gmail, and YouTube, it’s actually surprising that so few people who have registered for Google+ are using those more popular services on a daily basis — only 60 percent. After all, remember that a lot of Google+ users accidentally became Google+ users only because they were already attached to another Google service.
( via Venture Beat )
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