As Bettany points out, "It's clear from the detail shots that the iPhone 5 produces sharper photos with more accurate white balance, contrast, and saturation." She took photos in three different situations -- a well lit macro setting to test detail and quality, a skyline shot to test sharpness and saturation, and a candle list low light macro photo to test noise.
The results are amazing. I was surprised by how much of a jump in quality the camera received in the iPhone 3GS from the previous two generations, and how the iPhone 5 camera seems to have resolved some discrepancies in white balance that existed with the iPhone 4 and 4S. I can't wait to see what the next-generation iPhone will provide for iPhoneographers.