I had blogged how clean the installation of a chassis is with needing only 4 cables for I/O and 4 power cables. Via twitter someone asked for a pic of this and I realized I did not have one posted. I have added this pic to my Picasa page that contains about 50 UCS pictures (it is the last one).
Note how open the airflow is when you only have a few cables to deal with. You can see they were paying attention to this detail on the fabric extenders and where the power plugs into; all of the openings.
You can also see I am only using 2 of the 4 possible ports in the fabric extenders (FEX). The options being 1, 2 or 4 connections per each FEX.