Valve has announced that they will bring the 4 Majors format from CS:GO across to Dota 2 at the end of this year.
The announcement was made on the Dota 2 Blog and reveals that Valve will sponsor a major Dota tournament in the Winter, Spring, Summer and Autumn. The International will presumably remain as the summer event, and it wouldn’t be surprising to see the Dota Asia Championships become the regular winter event.
The first major will take place this Fall after TI5, more information will be announced closer to the time.
Valve has said that they will be working with third parties on the tournaments, so don’t be surprised if events such as ESL One or StarLadder become majors.
In the blog post they also mentioned there would be set player transfer windows in a attempt to stabilise rosters. They also confirmed that 6.84 will launch in the next few weeks.