Proof is right here. Below is Best Buy's huge discount on the RIM Playbook ($299 sale, normally $499). Despite that 40% discount, the Playbook is *still* 50% more expensive than the Kindle Fire. And that's before you begin comparing the two devices... I would pay a premium for the Fire vs. the Playbook.
Product is clearly important. But for mass consumption, price wins. And Amazon has won the non-iPad market by radically undercutting it.