Yeah but you cannot compare GoW2 with R2 in terms of sales. they're not playing in the same league. Only a few games can compete with it, I'm thinking about final fantasy, gran turismo and GTA. But talking about the price again, it really is a barrier. When friends come home playing ps3, I ask them if they plan to get one soon and the answer is the same: "I want one, but 400€ is way to expensive, I'm waiting for a 100-150€ price drop".
A similar price drop will have more effect than all the resistance, killzone little big planet or whatever.