Blizzard will be opening up the closed beta for Legacy of the Void starting on March 31st. They are adding some really bad-ass looking units starting with the Protoss Disruptor which looks totally over powered in the video. Blizzard is great at balancing so I imagine it won't be quite as destructive but if used properly? Blizzard also added the Cyclone a new unit to the Terrans which is a tank that locks on to an enemy unit and can fire while it moves. I can see the Cyclone being a very important part of Terran harassment in Legacy. Zerg multiplayer finally gets the Lurker back and Blizz added a new Ravager unit that can drop Protoss shields and attacks with a damage over time corrosive bile.

The video focuses primarily on the multiplayer updates but you can image how the new Protoss units may effect the single player campaign. Blizzard still hasn't talked about a release date so hopefully they talk about that at this years Blizzcon in November or sooner.

http://us.battle.net/sc2/en/blog/18291111/legacy-of-the-void-beta-preview-3-18-2015