ESL and DreamHack have announced that they will be performing a Fusion Dance, and are now operating under the same company structure shocked pikachu face.
They were already sister companies owned by Modern Times Group, so not much will change for you, the viewer, except for maybe events with frickin' laser beams attached to their stage.
Inside the company is a whole different story though, where plenty of people will probably have to change their @dreamhack.se email signatures over the coming days.
ESL Pro Tour had already created a strong link between the two tournament organizers, and so the merge won't have much of an impact on the pro scene either. Let's just hope it doesn't turn out as chaotic as the merger from The Office.