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Facebook has set itself up as the leading identity provider on the Web, with more than 2.5 million sites that operate Facebook Connect and social plug-ins, and something like 700 million active users. Now Apple is propping up the smaller–and different–Twitter as a competitor.
Twitter has 200 million total accounts–it doesn’t specify how many of them are active, or how many of them are real people. Apple, coincidentally, has sold 200 million iOS devices total.
Path CEO Dave Morin, who knows firsthand the challenges of social log-ins from his photo-sharing app, tweeted during the keynote yesterday, “Twitter is the luckiest company on earth today.”