The Path of Exile Website announces this weekend will be an open stress test event for the upcoming free-to-play action/RPG. They have a FAQ with all the details on how this will work, and offer the following overview: "The game has added a host of new features and content recently. The latest version adds a challenging Act Two boss fight, weapon swapping, and a new end-game system featuring Maps whose properties, risks and rewards can be modified by players. There is also a new layout for the game’s passive skill tree which features over 1300 skill nodes, allowing highly customized character builds and hybrid classes."