Disney is starting to release information regarding the new Mission: SPACE pavillion at Epcot. I was a member of the team that developed the innovative game Space Race, located in the post-show area of the building. Here's what has been revealed thus far about the attraction:
RACING THROUGH SPACE — Guests become members of the Mission Control team when they engage in Space Race, a high-energy interactive game that explores the teamwork needed between Mission Control and astronauts in space missions. Two teams work against one another to fix problems on their ship and be the first to arrive at the race destination. The Mission: SPACE post show, powered by HP, extends the adventure of Mission: SPACE, a Walt Disney World attraction set for liftoff at Epcot in 2003. Copyright 2003, THE WALT DISNEY COMPANY.

And from another source:

Two teams compete against each other in a race to send their rocket from Mars back to Earth. Nearly 60 people can play the high-energy game at one time.
Disney have officially announced that the preview date for Mission: SPACE is August 15 2003, with a full official opening date to take place in October 2003.

More information available at the official Mission: SPACE web site.