The game is a military simulation that teaches players about real-life military strategies and the role of the US Army in the real world.
The game itself is currently being put together using the Unreal Engine 3, the same engine behind games like BioShock and Mirror's Edge. It will apparently be looking to include all the best features of the previous games, but will update player arsenals to be more in-tune with modern day.It's basically another propaganda game but we can't complain as it will be available for free.
America's Army 3 is also set to up the propaganda too, using 'pride moments' to mark special achievements for players. These pride moments will typically take the form of slide-shows and movies showing the best the US Army has to offer and how well your achievements mesh with that.