We've been following the saga of SOE's free-to-play MMO, Free Realms, for some time now. First, it reached one million a mere 18 days after release, only to add another million in May. And, as if that wasn't enough, another million folks signed up a month later. It appears the game has no ceiling, though, as SOE president John Smedley told Comic-Con attendees (via Gamasutra) that the game is close to five million users now.Smedley attributed the success to the free-to-play model (uh, you think?) and said that folks have been surprisingly receptive to microtransactions. Because of this crazy rise in popularity, The Joystiq Hall of Science[TM] has stepped in to offer its own projection. According to our figures, we're estimating the game will have 17 billion users by Columbus Day of this year.

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