It's interesting that camera quality is so important for people, yet I find it difficult to find information on image quality beyond how many megapixels the sesnor has. The least they could do is tell me the sensor size/aperture size too.
You really have to search the specialized review sites to find good comparisons on image quality.
Not sure exactly what this references, but Apple actually gives fairly specific information on all of their iDevices cameras—on the Apple product page it specifically states 5 lens elements and an aperture of 2.4 for the iPhone 5. And 4 lens element and an aperture of 2.8 for the iPhone 4.
That's because the general public has been trained that more megapixels = better pictures. It's like horsepower in cars, or thread count in sheets.
We're starting to see manufacturers differentiate on aperature and other details. Nokia talked about how their mechanical stabilization allowed for longer exposures, etc. etc.
But when somebody asks me if the camera in my xperia s is any good, I still respond "yeah, it's 12 megapixels".
You really have to search the specialized review sites to find good comparisons on image quality.