I'm somewhat late in posting this (the story appeared Monday), but still.
3 Million Users.
This is a F2P MMO created and produced by Digital Extremes, an Indie Developer and it is quickly picking up steam, especially since Update9 came out this past week.
3 Million is not bad at all (What is WoW these days, 9mil or thereabouts?).
And the game is still in Open Beta.
Edited, Jul 19th 2013 11:40am by Lyrailis