Major League Gaming just wrapped up its Spring Championship this weekend. With four million viewers online and over 20,000 viewers and participants at the venue, it was easily of the biggest video game events to date. It featured three separate StarCraft 2 tournaments: the Battle.net World Championship Series USA National Finals, the MLG Spring Championship, and the KeSPA exposition tournament. On top of the e-sports features there, Blizzard offered game stations with Heart of the Swarm multiplayer and unveiled a lot of Heart of the Swarm information. The beta will be available very soon.
Blizzard produced a nice video demoing the new units and main changes to existing units. It offers a great overview: