There will be communication with the outside world via radio and email, but radio communications will be delayed a full 20 minutes as they would be on a real interplanetary mission and emails will take twice that time to get through. Both will be disrupted periodically, because what's the point of locking six men in a container if you don't mess with their heads a bit?
http://www.popsci.com/technology/article/2010-05/first-crew-members-selected-520-day-simulated-mars-mission - via mentalfloss
From the Upcoming ueue, submitted by nmiller.
http://www.popsci.com.au/2010/05/first-crew-members-selected-for-520-day-mars-mission-simulation/
I hope that they'll hose out the blood at the end of the "mission".