The June 8, 2005 edition of the Hollywood Reporter has an article on the Letterman Digital Arts Center. CTO Cliff Plumer discusses the infrastructure for the site including this being the biggest 10 gig network in the world by Cisco, plus capacity to handle 4k images and video.
It mentions also that the move will take between July and September and the site is already partly operational with 20% of the frames from ILM rendered there. You can read it here:
Lucas units find a home in Presidio (PDF, on page 8)
Thanks to Terrell for the sharp eyes.