What is the difference between these two sites?
Since the core rules are likely to be the same, having a more "official" source of rules seems moot. Are there any distinctive differences in content offered?
e.g. Does d20PFSRD offer anything that the PRD doesn't (or things that should be paid for), or does Paizo miss out on anything by people using d20PFSRD that they can invest in making new materials?
Is there any real objective reason to use one instead of the other?