Path of Exile has spent a few months in open beta, and is currently working on a full version to launch. It's a long way off, though, as the game's 1.0 release is still six months away according to Grinding Gear Games co-founder Chris Wilson.
Wilson told Joystiq that the game is currently sitting at roughly 2 million registered players, and the team has been providing regular patches and bug-fixes as it prepares the final version. Once the full version launches, Grinding Gear plans regular expansions "over the next five to ten years." He didn't give a timeline for expansions, seeing as smaller events can be updated quickly, but he said major features like new acts would be "probably a once a year thing."