Blizzard will host a launch party in Los Angeles this evening to kick off tomorrow's launch of the new Reaper of Souls expansion for Diablo III, their action/RPG sequel. The add-on should go live around midnight eastern time, and right around that time Game Director Josh Mosqueira and Senior Technical Game Designer Wyatt Cheng will be on the Diablo Twitch channel to celebrate the launch. Word is: "Josh and Wyatt will be coming to you live from the altar of the Vibiana to share the highlights of the evening's event and give a deeper look into Reaper of Souls and its development." This page has launch details for Reaper of Souls, including when it will be live in various territories.