Personally I have great difficulty believing some of the figures that are being bandied about for litecoin FPGA.
Can you share a link to the threads with your bandied about numbers? I haven't seen anybody say anything that outrageous here.
These numbers are from bitfury somewhere in the forum here. While its not so easy to verify the numbers i think he is a quite skilled HW-Designer so i would careful with 'ABRACADABRA'.
http://bitfury.org/