Grinding Gear Games will be pushing their next major patch update out the door for Path of Exile at the start of December.
The 2.5.0 patch is scheduled to hit either on 2 or 9 December. This 2.5.0 update brings the new challenge league along with other updates, but the major point to note is it brings the DirectX 11/64 bit Path of Exile game client.
GGG are planning to launch an opt-in test for the DirectX 11/64 client during their 2.4.2 update which releases early next week. The update also adds three new channelled skills (Blade Flurry, Scorching Ray and Blight). There will also be bug fixes that were planned for 2.5.0 in this update.
The 2.5.0 update will be the final patch in 2.x series, with the 3.x series beginning in 2017.