nVidia's mostly paper launch of the GTX 275 has yielded some unexpected benefits for AMD.
Due to the limited number of actual cards (only Palit has them in Europe) and the general availability of the HD 4890 AMD is claiming a 30 to 1 sales difference.
nVidia is keeping pretty mum about this only saying that the AMD figures do not match what they have. Of course they have not revealed what figures they do have but then again AMD has not exactly published theirs either.
Read more here.
AMD - which, like Nvidia, sells GPUs to partners rather than flogging complete graphic boards - claims this particular piece of SpInfo comes from two of the largest resellers in Europe.
Although our INQuiring minds may be inclined to take AMD's claims with a large pinch of salt, it's also worth bearing in mind that good launches tend to put a few thousand cards in the channel, whilst mostly-paper launches barely manage two dozen.