At the D23 "Destination D" event Bob Chapek, the Chairman of Disney Parks and Resorts said that major changes are coming to Epcot. A tweet from @DisneyParks cites Bob Chapek telling Imagineers to, "Dream Big" when it comes to Epcot changes. As part of this discussion, Bob Chapek also referenced an increased presence for the Society for Explorers and Adventurers which has been part of the backstory of several Disney attractions and areas throughout the world.
Chapek also emphasized that the changes would maintain the original vision of the park. We have been tracking the evolution of Future World rumor here.