I want to know what more advanced bodies give you that lesser bodies won't. I know that more advanced bodies will give you things like better IQ, FPS, and AF speed, but what else is in a D300 that a D80 doesn't have that's worth dropping nearly $1K more on? I hardly think IQ, FPS, and AF should be so expensive. This is just out of curiosity. I know that generally the lens matters more than the body, but I do want to know what matters in the body.