You see I can understand if the cost of extra shipping adds £10 or £20 to the price
I'm not really placed to have a discussion about graphics pricing because, unless you have a problem with the pricing of a motherboard or a system, I have no influence, but I would like to clarify a couple of things to prevent any confusion/misunderstanding.
Nobody ever claimed that shipping cost was entirely to blame. I raised it as a factor, mainly to explain why items naturally get a bit cheaper after the demand dies down and slower shipping methods are viable. I see many a comment along the lines of "oh, they'll be cheaper in a few months time" and this was aimed at those mostly. The shipping differences mean that our costs come down too.
Gibbo has been clear about his thought processes over the 6800 pricing in this thread already and the shipping differences will have had some impact on why Gibbo considered the margin on offer, at MSRP, to be unreasonable.
As far as the actual cost difference, again, I can't speak specifically for cards, but the difference between express air and sea container on my motherboard orders reached as much as $45 per board recently vs $2-3 per board via container.