Wow 12 ghash with usb's for about 9k$.While I can appreciate the low power cost I think id try to just go with a blade for 6500ish. Nice setup tho.
$9k ?! What is this fiat you speak of ? Have been reinvesting Bitcoins i've mined over the last couple years into upgraded hardware
http://www.amazon.com/gp/product/B005NGQWL2/ -- 10 port hub in the pics
http://www.amazon.com/gp/product/B003XN24GY/ -- Fans used. Not sure these make a significant difference in cooling, but I guess it's better than no airflow at all.