Auto-exposure is programmed to set the overall brightness of a scene to 18% gray meaning it can easily be fooled by any scene with lots of whites or light colors or blacks or dark colors. As a consequence, experienced photographers are used to seeing under- and over-exposures, recognizing the conditions where this could be a problem and compensating for them. In my case, if the exposure of my XTi was off by some small amount, I'm not sure I'd even notice let alone find it to be much of a problem. The problem with this "exposure issue" is that those who are used to using completely automatic point-n-shoot cameras and who don't understand how auto-exposure works are apt to blame the camera so it is very difficult to judge the imporatance, if any, of this issue.