Here are some renderings of the new C/D terminal at Dulles,

http://www.degezelle.eu/en_public_buildings.html

http://www.pgal.com/portfolio/washin...rt-tier-2-mid/

http://www.kpf.com/project.asp?R=1&ID=60

It looks like it will be a nice terminal, and they seem to be moving towards trying to make it a reality, although I think it won't happen for another decade or two because no one wants to pay for it... unless they raise the tolls on 267