The game was originally slated to enter beta this month, but the team decided that it was "too dangerous to launch the open beta over the Christmas period and Southern Hemisphere summer holidays when many of [the] staff will be away," lead designer and producer Chris Wilson explained on the game's official forums.
According to Wilson, the extra time will allow the team to do some extra polishing and testing before new beta testers are admitted to the servers. Until the beta goes public, current alpha testers have been asked to "push the [current] patch to its limits," he wrote.
During the holidays Grinding Gear plans to host more community events, and hopes to add support for pre-paid Paysafecards before the open beta begins. Wilson also announced that forum titles given to players who purchased beginning supporter packs will be unavailable once the current closed beta ends, making them early-support exclusives for Path of Exile players.
Grinding Gear will also begin sending 500 closed beta keys to random beta testers each day to bring more people into the current testing phase.