[matthew]

But your definition of "acceptable image quality" is likely not the same as mine. For me, I want image quality that allows the production of large, wall-hanger prints, not just 8x10s.

Absolutely. "Acceptable" is the level at which a person is satisfied, and it'll depend on the individual and will change from use to use. Additionally, I added the qualifier that it's generally comparable at each price point. I'm under no illusion that what is acceptable to someone looking at a 16mp 1Ds mk2 will be equally served by a 6mp Dribble: a 12mp D2X, maybe, but those aren't really the same price bracket, either.

If I were only concerned with 8x10s I would have kept my Digital Rebel.

I'll let other people defend the 6mp group... I'm only at five, so what do I know? But the image quality spectrum also goes the other way...

I was recently at a marathon where I was shooting alongside someone using a D2X. His largest output was going to be an 8x10 -- he was a pro and was going to make a lot of money that day -- so there was no difference between our image quality needs. I guarantee that my camera wouldn't have met his performance requirements. (I shot under 1GB that day. He was carrying 40GB of cards, and was worried about running out.)