Sure didn't look that way in 3Q. Looks like about 15k Opteron processors sold compare to about 40k+ Madison I2s. Considering the selling price of IPF systems seems to be 5x to 10x higher per processor and it is obvious why there is such a huge disparity in OEM and ISV support enjoyed by IPF and Opteron.
The amount of sales is a function of features, price, marketing and several methods to convince potential customers. For the last 2 points you'll have to invest a lot of money (including the lowering of prices).