John Smedley is, of course, as pleased as punch: "This benchmark is an honor and a true testament of SOE's success with free-to-play games."
It turns out that the PS3 was a godsend for the already hot title, as over three million additional console and PC players jumped on board the Free Realms train following new platform's release. While SOE didn't comment on how many of those new players stuck around after the entire system was taken offline for the better part of a month, this milestone speaks well to the game's popularity.
The company is not releasing information as to how many of those 20 million are still actively playing the game.
[Update: Clarified numbers on console players added after the PS3 launch.]