Five months ago the expansion, Sacrafice of the Vaal was released for Path of Exile, and excellent expansion that added a large amount of content from new item types and areas to a brand new final boss. The plan Grinding Gear Games had set in motion was that they would release a new expansion every six months, and thus far they have made good on the promise with the announcement of their latest expansion coming this August.
Over the course of this month and leading into the next, the development team will be releasing teasers of screenshots, lore, items, skills, areas etc etc leading up to the release. Their was an insane amount of hype leading into SoV and i expect this new expansion to be just as big of an event. Judging by the new banner and side images, i imagine the expansion may be more focused on PVP and guild vs guild.