It is an interesting design for a high density setup. Let me mull it over some more and I will get back to you with some thoughts.
I look forward to your feedback.
Latest update 4/29/13: I have found a Linux developer that will put together a light version of Debian that will specifically be developed for this rack. It will allow the entire system to run from a USB key that will come pre programmed with Cgminer, optimized for 6 GPU per motherboard with a very light OS and graphic interface to optimize the Hash/Watt. It will also allow the operator to monitor the rack remotely. AUTO INSTALL and AUTO RUN (no computer knowledge needed, 99% Plug & Play).
I am interested please keep us updated