The Overwatch World cup will be held at Blizzcon and will be a marquee event for Overwatch esports. The world cup for 2016 was massively successful and showcased the talent of the young Koreans.
This year Blizzard put forth the decision to have a committee which will decide the teams for each nation. They have finally released the names of the committee members for each nation. The members present a mixture of players, team owners and content creators.
You can read about all the committees at Liquipedia.